Guangzhou Liss Optical Instrument Microscopes: Model L-201; Chinese National Instrument Import Export Company Brand.

By David Christmass

First published in the March 2010 edition of Micscape Magazine. Major update October 2014.

Introduction to the L-201.


Beck Standard Model 1


China National Instruments


China National Instruments

Euromex 5225.jpg

Euromex Model SE. 5225

Paralux L-201.jpg

Paralux L-201 or Ref. 60-6202-9

Ask anyone to describe what they envisage a microscope to look like today, and the picture that they would present would be something probably approaching that of the images shown on the left. They look similar, but there are subtle differences in the designs.

The Universal Compound Monocular Light Microscope is probably one of the most familiar designs of microscope, in the world, and of this family, the Model L-201 is exact to that traditional standard and pedigree. It has its roots in a British Design Patent, (Becks Standard Model 1, source: Allen and Hanburys. Pre World War I), was adopted, adapted and then modified for the United States Market by American Optical USA, where the microscope became more fully bodied to suite the American market. The microscope sold in the AO catalogues around 1934 as the American Optical design Standard Lab Model. One of the distinquishing features of this influence, was a movement towards a longer mechanical tube length of 201 mm, just under eight inches. The microscope also gained some more mass, weighing in at 4 metric kilograms, just under 9 lbs.

In the 1920's the stand looked more like a Nikon, with Art Nouveau styling much like the original Olympus Showa design. But whereas Nikon designs tend to be formed of curves uppermost to the stem, the Beck, and American Optical models were at first more linear and blocked upon the stem. During the 1930's this styling took on the Art Deco influence under American Optical production in the US, and this influenced the styling of Zeiss microscope production in Europe. In Europe, the microscope was standardised and existing models of microscope with longer mechanical length tube were refitted to conform to the 160mm 6 inch standard, by replacement of the ocular tube, from 85mm (inclusive of the 5 mm concealed thread) to 45mm, granting a total mechanical tube length of 160mm, not 201 mm, as originally specified by the US revision of the Beck. In its original longer form, the microscope could be applied to metalographic, and histological biomedical applications. That humble Beck Standard Model 1, had grown bigger in size, and earned wings, but not quite so in Europe, that still maintained the 160mm or 170mm tube lengths.

After the Second World War, production, was reinitiated in Japan, and some of the antiquated designs of the American Optical pre Second World War period were transferred to Japan and adopted and improved by Olympus Optical Instrument Co. research specialists, under the Post War redevelopment alliance of Japan and the US. One of the significant aspects of the Olympus design was the restyling of the horseshoe base to give the microscope more stability in situ. The former Y shaped base of the Spencer tradition, became a U shaped base, and the blocked ends of the microscope acquired the rounded bevels at the front.

Through the partnerships of this design evolution and under the management of the Olympus Optical Company, with its established brand name, and its multiplicity of pseudonyms, such as OIC, Minolta, etc., and an ever extending international support facilities, that were based on the older versions of American Optical design patterns, the G series microscope saw its greatest success in the International market. The many fold manifestations of the G series stands, include the GA, GB ,GC, GK, the Olympus POS, the HSC, HSA, HSB, and ST models that were produced for the educational market. Further, OSK models embrace the same design compatibilities such that stands under this brand find purposeful function in and about atomic research and environmental analysis, and aviation industries.

Its advantages are several, ease of maintenance, ease of use, extremely high power capacities, price, and uniformity of structure, compliancy of parts, compliancy to mass manufacturing processes, which make this microscope, affordable, and principal above all others for life long use. There may be some that dispute this, but I shall leave the critics hunting for that annoying little screw part, that is unique to a microscope, 10 years down the line, when the fads and styles of the day have moved on.

In the British Isles, the Post War era was not good for the microscopist. The main major microscope manufacturing crafts had been annihilated during the bombing of many of the cities that had manufacturing facilities in their centralised industrial bases and those that never suffered greatly from damage during in the war, failed later against competition from overseas mass manufacturing processes which prevented their return. Many of the famous brands of English made microscope survived only in name, there were still many retail shops, and craft bases in the family business, but through successive mergers, names such as Beck, Baker, and the microscopes of, Cooke, Troughton and Simms, came to be unified, gradually, under one main industrial base, ostensibly Vickers. That Beck Standard Model 1 evolved to be, the Vickers, Model 26, via the Beck Baker Cooke Troughton Simms mergers, till finally all models took on the G series form, from American Optical influence.

By the start of the 1970's, the G series microscope had come to be manufactured in China, Guangzhou. There were two principal routes to importing the Standard microscope from overseas to the United Kingdom. One was through the Soviet Importers Technical and Optical Equipment London, who imported Zenith microscopes, and the L-201 was in fact imported not from Russia, but direct to the United Kingdom from China, to TOE. The other route, was through Olympus UK, who imported products via Japan. At this point of time both the G series and the Zenith P-6C were ostensibly the same item from the same factory. In practice, however, it was found, in application to comparison microscopy which uses a brace to bridge two microscopes, that the microscopes supplied from Japan, where less robust than those that shipped through TOE.

Those microscopes that were used for comparative microscope, were found to decay in use. This was investigated, by Olympus, who, suggested that the part which forms the fine focus, lateral to vertical support, a triangle that looks a bit like a Chinese dragon, be up rated to a smaller shape, of L formation. So the parts were uprated on Olympus microscopes, and the G transcended to become a HSC. But the Zenith microscopes which were more robust, were not attended to, and still carry the original dragon part. In point of fact, after the release of the HSC, the problems were not wholly resolved. This was because, in application comparative microscopes skewed with the brace, tending to be not horizontally moved in tandem on both microscopes.

Rather than pursue the matter even further, Olympus made the decision to drop the G series microscope and HSC, altogether, recommending to its customers, newer products, that did not present these problems. So there upon there came to be a difference between those microscopes useful to Forensic ballistics, and those microscopes useful to the Education sector. Those schools that had backed Olympus, ostensibly lost service and support, when the new range of microscopes were unveiled. During the investigation, which was both Civic, and Legal, as it concerned the UK's Police forces, it came to light, that Olympus at Honduras Street, where taking back microscopes, and sending them up the road to Technical and Optical, for servicing, rather than sending them all the way over to the East, for repair what we now call as subcontracting. During the dispute about liabilities, the engineering team at TOE was criticised for its failing to rectify the problem completely, when asked by Olympus, who had to resolve the matter, themselves, with their own, albeit unsuccessful update to the cam part. As the disputes came to a final resolution, the justices concerned ruled that each company should deal with only, their own microscopes.

On the one hand, the teams at TOE went on strike, against being asked to perform engineering tasks of repair and for microscopes used in application for which they were not suitable for, and then get criticised for shoddy workmanship. All professionals at TOE simply refused to carry out any work or repair on the Standard microscopes, even those in the educational sectors. On the other, Olympus lost a good deal of trading capacity, in the education sector, because institutions were simply not prepared to put up with a 3 month return to base warranty from the Far East. That behaviour was also motivated by interests within the Japan mainland who desperately wished to switch from the Standard microscope, to newer designs. So Olympus introduced a newer range of microscope designs, from its other plants. Manufacturing in Guangzhou, which is also known as Panyu, Gongdong and in Japanese Canton, was at first, under licence from Olympus and then later, the microscope was independently marketed from the factory under Chinese National Instrument Import Export Company branding, when Olympus ceased to include the microscope in its portfolio, around the time of the introduction of the Vanox range in 1972.

In the UK, by this time, much if any of the traditional microscope production had ceased, microscopes from the East started to be branded, with more familiar Western brand names. There were mergers and take overs, and as the product of the fad of European integration, the trend to have more confidence in these artifical brands of Eastern products, grew. For example, Philips microscopes bought out what was left of the traditional family businesses, of yesteryear, and new designs were only the products of Vickers, alone. On the L-201 microscope, the logo of circle and sphere denotes a trademark commonly found the front of the Lomo catalogue, of the Russian company Mashpriborintorg: even though the script clearly states the product originated from a Canton, Guangzhou factory: it is the sign which signifies the microscope originated through the TOE route, but not necessarily from Lomo, or via Mashpriborintorg themselves. TOE obviously sourced the product direct, from the East. Phillips shut its microscopy manufacture in the early 1970's, and during the 1990's Vickers also ceased its local production and innovations in design, like American Optical, many of the UK microscopy manufacturers simply ceased to exist, period, the scales of economy being to greatly swayed towards Eastern imports. All that remained was the crafts and skills of enthusiasts and restorers, to support both education and industry.

In contrast, in China, and Japan, the story is very different. The Guangzhou company still had to produce microscopes, even though Olympus had chosen not to furnish Europe with G series designs. But the G series design within Olympus was still required, and the continuum of production in Guangzhou provided two functions: First, the POS microscope appears not to have been deleted from the Olympus catalogue, even up until 1996. Second, with so many microscopes in the market place, support connections still required there to be manufacturing resources, for parts. Indeed still today, Guangzhou can provide a multiplicity of parts and accessories for their models.

When Olympus OIC, Optical Industrial Company, revised and updated their microscope range at the start of the 1970's, the G microscope range was dropped from the portfolio of the Olympus showroom to the West, but it never vanished entirely.

Western educational establishments, with a commitment to the microscopes already in their possession were left confounded both by the decision by Olympus Optical Instrument Company to drop the microscope from its portfolio and also confounded in terms of their requirement for support: after all, up until that time, Olympus had provided support direct. Even more surprising, it is to find that original, OIC G Series and Olympus stands are still available today, to buy new in some areas of the extensive manifold branches of the Olympus company, notably Olympus Optical of India.

Guangzhou still have great success, with the L-301 a quadruple version of the L-201. The production licenses for the production of the microscope stand rests with the Guangzhou Liss Optical Instrument Factory, Guangzhou China, and the International trading rights of International distribution, rest with the Chinese National Instrument Import Export Company of China. The official China National Instruments L-201 microscopes bear the London underground type globe and banding trademark that is shown below. The official Olympus microscopes of the same form bear their respective traditional Olympus trade mark.

The Guangzhou Liss Optical Instrument Factory, which is now the Guangzhou Liss Optical Instrument Company, therefore, plays an essential role in supporting all merchants throughout the world, with optical products of exceptional quality. Forthwith I refer to this manufacturing source in China, as GLOIC. The L-201 and more recently the L-301 are Industrial Grade, and conform to the original specifications in parts and performance introduced under the influence of Olympus in China.

The Guangzhou Factory is unrestricted in production and is currently finding tremendous success with a wide portfolio on wonderful new products, maintaining all attention to detail of their craft, pedigree of exceptional design and conformity to the norms and conventions of the existing market. Consequently, Olympus G series HSC series, parts and accessories are completely compliant to microscopes produced by the Guangzhou factory, and distributed by China National Instrument Company. Microscopes from Guangzhou are available in the west from GX optical who maintain the presence of the Occident in the West.

If I were to be critical of the failing of this microscope it would be in the arena of information and specifications of manufacture, part numbers, and conformity of standards, not much appears on the factory web site detailing the construction patterns and standards and documentational support, not in the construction of its design pattern. More has to be done in that arena of China, for provisions of Western technical support requirements.

The China National Instrument Company Microscopes from Guangzhou differ in two ways to the original microscopes offered by Olympus. The round stage platform of the L-201 does not have the provision of holes to accommodate a slide measure super stage as standard. The lower side of the filter unit has a swing filter, and is not the interchangeable filter unit on the original Olympus Abbe. Both of these inconsistencies can be overcome by fitting the appropriate stages or accessories for the task in hand if and when required. Phase contrast sets, for example, are available either from Paralux, or as accessories from Yujie or GLOIC. Olympus platforms can be fitted to accommodate superstage accessories.

The original L-201 microscope as imported by Technical and Optical Equiptment, and marked with the London underground Mashpriborintorg type trademark, from Guangzhou, complies well to the Standard RMS microscope and to relevant parts of the British Standard 7012. It would be difficult for me to say that modern recent versions of the L-201 such as the XSP91-201 and the Wedmore SP14 or the ones from the Midwest don't also comply, but they seem more lightweight in design, less robust, and it would be correct to advise that they don't comply so well to the Standard, as the original ones shipped over through TOE.

The construction of the European community during the 1970's sought to promote an improvement in international trading about its members. Nobody involved in that partnership, ever envisaged that in the formation of membership peoples there would be political influences about its leadership which would result in stoical attempts to exclude trading in the Occidental, Australian, Indian or American Continents in preference to European interests and in prejudice to those outside its fence.

In point of fact, as Companies sought to redirect the manufacture of commodities outside the European community, mandates were passed by Eurocrats to impose trade restrictions to nations outside of that collaborating group. Covertly, and absurdly, for a peoples who profess to exist in the Free World of the West, those consumers present within the European community were misguided and covertly prevented from being exposed to goods and commodities from outside their immediate economic area.

As a somewhat despotic mechanism to maintain the supplies of trade in microscopes in schools and industry, even, in the face of restrictions in international trading, a multiplicity of European microscope manufacturers sprung up all over Europe, all either assembling microscopes from parts obtained outside, or actually creating microscopes from first designs of their home base, thereby bypassing the import restrictions levied by European leaders, so, during what can only be described in Europe as the Olympus crisis down under: that time in Europe when the basic school microscope was removed from the portfolio of goods accessible to those in the service field, many European models appeared to the fore.

To make matters worse, many of these new designs adopted a metric pattern for tooling, abstract to the traditions of optics which lend themselves to more accuracy being dependant upon optical light paths. That metric designs maintain the continuum accuracy has less to do with improved design within European metric manufacturing processes, and more to do with the requirement to coat the lenses for optical correction. To many, having to purchase a bespoke cleaning fluid from only one source is a literal pain to the butler, compared to the more generic designs which can be cleaned with generic cleaning fluids, openly accessible and unrestricted by single market sources.

The manufacture of screws and service parts conforms to a metric pattern of a form on this microscope, but it does not conform to what is commonly known as the ISO standard for metric thread patterns: officially, that standard is the French metric standard, and is excluded in most high end mechanical components made under Japan standards Industry: the far east, that is, ostensibly, Japan and China, and parts of Southern Korea, have their own standards of ISO metric threads based on the German Lewenhertz metric standard which ostensibly makes the thread patterns of screws conform and available to comply to American standard thread patterns, in terms of pitch. The exception of course, is the microscopes compliance to RMS standards for objective threads, and ocular. Sometimes, on some components, the microscope presents the metric fine pitch threads, most notably on the ocular tube connection to washer, and a course thread on the larger washer insert to the stem. Of course, all these areas comply to ISO standards for that specified area of manufacture.

So in summary, there exist now, broadly speaking, a division in Europe between those that use European microscopes and those that prefer the traditions adopted by Japan and the United States. America, China and Japan are big, sure, its a gods best bet to stick with them, and not lose. And the story so far is one of whether you make the choice to base your optics upon a film or prefer to have your optics free from films.

The Europe camp consists of a consortium of makers. The Euromex Model SE. 5275 has a round, adjustable stage, the Euromex Model SE. 5225, has a traditional square stage, but neither of the Euromex brands of the L-201 based designs, in the Euromex S series ships with a condenser, or the range of optics which extends the L-201 to the 2000 times magnification of the Wedmore of a similar base. The Euromex Model S series, as it HAS maybe IS (not quite sure why the microscopes vanished along with the service support information from online recently) being marketed so far, is ostensibly an original Guangzhou factory microscope stand, but with the rotor replaced by a rotor that accepts European optics, and remanufactured within Europe, from parts supplied from microscopes from the East. It is a hybrid design, of a Chinese base, and European optics. It conforms to a pattern set by Euromex, not by the factory manufacturer Guangzhou in China. That is important in consideration of fitting oculars, objectives, and also areas of the turret rotator, as the rotator is replaced on the Euromex to accommodate, Euromex own objectives.

The Paralux brand of the L-201 microscope transcended from being an Olympus GLOIC L-201A to adopting the Euromex form, when supplies to Europe dwindled, during the Olympus crisis. Paralux are French, established, and old enough to be able to support both the Japanese traditions and the European traditions. Again the L-201 seems to be documented as available everywhere, but at the Paralux main site. It were as if, as soon as I write a link to a company, the company scraps the information provision. At present, the current Paralux model is called a Micro PCB and differs to the originall L-201 pattern.

The Euromex, Wedmore, and Paralux stands based on the L-201 differ in their ability to accept original Olympus stage accessories. Original Paralux L-201 microscopes as shipped from China National Instruments comply to the traditional standard.

The important distinguishing features in denoting the L-201 Olympus compatible China National Instrument microscope and the L-201 microscopes of Euromex / Paralux / Wedmore form are two fold. The GLOIC L-201 is cast iron, has a bar to the underside of the moulded base with a hole for securing to an optical table, and for packing in transit.



There are Two pairs of supports to the underside of the GLOIC stage platform. These differences make the GLOIC China National Instrument microscope compatible with the Olympus, but make the Euromex / Paralux / Wedmore forms only compatible as far as optical accessories. That is, on the newer models of Paralux, the stage mountings differ, so a new Paralux stage won't fit on an older original microscope.


GLOIC Olympus Stage bracket.

Obviously there are a few cosmetic differences between the Paralux and Euromex brands, but the inconsequential differences between Black or Silver, trims and knobs, is less important than ensuring that the power of the lens is good enough for the tasks placed before it, which in its original form both in 201mm and 160mm versions with Eastern optics, the L-201 is more that capable of achieving. The L-201 microscope from GLOIC is normally fitted with a ocular tube to conform to ISO standards for mechanical tube lengths of 160mm, but can be updated to have a larger tube, for metalographic applications, that require a longer standard mechanical tube length of the 8 inch standard, which is also very helpful for medical applications and more general inspection. In short the original L-201 microscopes that comply fully to the Olympus Japan pattern are a better buy, than either the Paralux or Euromex versions.

The Paralux L-201 Brand has a Paralux Model number 6202, and ships with more powerful lenses than the Euromex S series, and it also has a round stage and underside condenser.

Identifying Guangzhou Liss Optical Instruments

Identification of a GLOIC microscope is achieved by inspecting the top of the Stem. Original microscopes made by GLOIC carry a plate mark indicative of the production locale.

This is usually a logo, and also, a trade mark, that is proudly placed upon the device by its creators to indicate the care and attention the product received in genesis. A genuine GLOIC microscope carries the logo shown. The trademark shows China National Instrument company, which is the Import and Export facilities for supplies.

GLOIC Logo.jpg


Quite often it is said in support of branded products, that foreign imports, outside of Europe, are inferior copies of Western products, but, while that might be true of produce in the I.T. industry, it does not appear to be true of optical domain: quite often the reverse is true.

The original L-201 microscopes, as they have shipped from Guangzhou, China, to the West, via the China National Instrument company came supplied with a Wooden box, optical objectives of 4x 10x and 63x and a full range of eye lenses, 5x 10x and 15x, and an Abbe condenser. This is the configuration Yujie still offer as do Yuda the medical supplies company of China. The standard configuration as supplied by GLOIC conforms to the original Olympus specifications with 4x 10x and 40x achromatic optical objectives and a similar range of lenses. GLOIC are currently only producing the L-301 microscope. The microscope is fully part compliant with the former L-201 model, but comes loaded with four objectives 4x, 10x, 40x, 100x. Branded products or supplies via Western distributors may differ to this in offering these as optional extras. This is because, for the greater part of the past 40 years, much of China has been manufacturing these products on behalf of established suppliers, who place orders for vast quantities of a product, tailored and specifically branded to merchant specifications.

Many of the original L-201 microscopes were distributed by small, independent traders and retailers, who preferred to stock GLOIC products, because they were made available to their distributing networks and because they tended to offer, exceptional quality, unparalleled by the branded products of their price bracket.

Many of these shops were specialists, or Independent Camera shops, who stocked GLOIC Microscopes for their customers to buy because they knew that there was a common source of manufacture, of both branded, and unbranded, products from China: in point of fact, while I was engaged in trying to obtain a source for a manual for the L-201, one large distribution company responded to my enquiry, by openly and overtly stating, that my attention would be better placed contacting Microscope product manufacturers directly, which they said, in the greater part are largely all located in China! Of these, GLOIC is the Grand Daddy of production facilities: they manufacture, assemble, and distribute parts to other assembly plants for bespoke microscope designs.

Production of the L-201 in Guangzhou has largely been superseded by production of the L-301, which is the same base model but has a quadruple turret, which takes 4 objectives. It is perfectly possible to upgrade the L-201 to the L-301 standard by upgrading the rotor. Many of the accessories which are available suit both models An Olympus stage may be fitted to the L-201 and the model can then accept Olympus superstages and micrometers.

The current GLOIC model L-301 looks much the same as the Brunel Wedmore microscope, but I am advised by Brunel, that the Wedmore, is, in fact, not a product they is source from GLOIC.

From my personal observation, I can see that the stem of the Eye piece of the Wedmore, is a little longer than that on the L-201, and that the Wedmore has a different design of stage to the L-201.

That being said, I dare to suggest that many of the accessories available from Brunel, would also be suitable for GLOIC L-201, and the L-301 instruments.

Details of the Wedmore range are available from Brunel here, for education here, and from UKGE here.

Although there seems to be trends towards newer, safety first, designs of microscope, with stages that move with respect to a stationary stem, for all its advantages, I still consider the traditional design of the L-201 with a stationary stage, relative to an adjustable stem, better suited to work which involves micro manipulation tasks.

Manual matters

The most recent European distributor of GLOIC L-201 microscopes is Alaska Paralux of France. The Paralux product page for the L-201 might have been found at the L-201 product page and has to be reproduced here as a reference to the compatible Paralux accessories range.

The Paralux L-201 data sheet might also have been found on the Paralux site page, and is reproduced here for reference also.

An English L-201A manual, based upon the French Paralux L-201 6202 brand, is available for print and electronic reference from the Micscape site or from Paralux direct (they had my consent to distribute in support of the L-201 product English user base). (Special thanks is extended to Christophe Lavanchy, at Paralux, for sending me a Paralux French version to translate). The French version is available from Paralux France direct, so please contact their technical support, as I don't have rights to openly distribute the French version myself: the French manual is not my own work.

The Electronic edition of the manual is straight forward enough, all pages are arranged to view in order. The print version of the manual is designed to form a 16 page booklet. Please don't email and ask me to rearrange the pages in another order, they are correctly arranged as they appear in the file. Here are my findings on this matter.

For some reason, different printers, render the file to print in different configurations, so getting the booklet to print correctly is much dependant on your arrangement of hardware, for example, printing with a HP laserjet, using Acrobat Reader 5, seems to render the booklet as you would expect: set the output to print 2 pages to 1 A4 sheet, 1 page at a time, keeping the orientation of the page the same in one plane, but presenting the blank reverse side of the previous page for double sided print, once you have produced 1 hard copy, running off 50 thousand in the photo copier is not going to be a problem, but its getting there, if you like, you can put a bit of Monty python music on in the background, it will probably take you two hours and a Christmas tree to get there!

HP laserjet printers appear to grant full options to get the printed page orientated in the way you might expect. With Epson printers, and I don't know quite why, but my Acrobat Reader 5 version, does not allow the swapping of the pages around at the printer driver command level, so better results are achieved by orienting the file so that the back page appears first (top), and then the front page (bottom of sheet 1). This is achieved in Acrobat 5 by turning the print so it appears upside down before printing (rotate page 90 degrees twice in Acrobat); if you don't, the booklet you get will open the wrong way around. This is not a Epson print interface matter, I have always found their printers the best, and most other software packages allow for full options at the printing level and it is possible to select what page appears top, or bottom in 2 to 1 mode, except, for some reason, Acrobat Reader 5. I guess they have a preference to HP. This might not be the case with Acrobat Reader 4, or some other Acrobat Reader versions. In short summary, I have printed the manual using an Epson, using my original copy file, and after printing the copy through to a Acrobat pdf file and turning it upside down. I have also printed the pages with a HP. So it, IS, possible to create a booklet from this PDF file, but I am afraid you will have a bit of fun and games learning quite the exact way your setup will allow it: just like me! My apologies for that, there is not much I can do about the inconsistencies that abound in I.T.

Please don't email me with requests for English translations of other Microscope manuals, TEFL is not my business, or my hobby, and neither is I.T.: my linguistic efforts were a grace and favour action, extended as an enthusiast of microscopy, in support of the L-201; it seemed to me right that GLOIC having supplied me with such a decent product, and the French having blessed us with Pasteur, that the English speaking world should be blessed with a decent manual.

One final note on manuals. The L-201 microscopes that shipped to the UK, and sold in stores, sold minus their manuals, and I don't quite know why that was, the excuses I have been granted, ranges from the obligatory it aint ours and I cannot be bothered, to you dont know of what you speak, clearly after reading this page, that aint quite the truth. I have also been advised of water damage in transit and all sorts of other strange tales.

Please, if you have an original manual package, for the L-201 microscope from Guangzhou and are certain beyond belief of that, from what you believe is a genuine microscope from Guangzhou please scan it, and email to me direct, with a set of images, jpgs, or tiffs, and I will create a manual to open in Acrobat Reader 3 for all in support.

As far as my personal support goes, my references are direct and the truth. Thanks to Olympus, Jeff **** and Alan **** not to be embarrasing, for the HSC manuals from Olympus, and the parts manual from Olympus. These two manuals I have stashed for safekeeping on the master of Olympus archivists, Mr Alan Woods site. The majority of parts numbers, are compliant to parts on the L-201 microscope as it is originally an Olympus pattern, but as the L-201 was based on the G series stand, there are major differences in cosmetic parts, the knobs have flanges, the cam is different, but for screws, and platen parts, most of the part numbers listed, on the service manual should allow for a more exact location of the correct parts. Also on the site, is the basic user manual for the HSC. There are also manuals available for the Paralux microscope, which I personally translated from French, documented on this the micscape site, and it would be helpful if Euromex presented their service information, online, for service people.

The L-201 is not suitable to support the weight of a brace, in ballistic forensics comparisons, please be advised of that, world over, the skew of independent adjustment, undermines and distorts the thread of the course mechanism, till some poor bugger gets the blame, even on this solid and sturdy item, which is more substantial than the Tokoyo produced items, ie, more delicate. If you need a comparative microscope, a ganged version in the uppermost region would be the better choice, with fine independant adjustments being made through movement of the stage not the stem that holds the brace tube. Check out CNOEC, watch for that particular, and when you get the chance, buy an dedicated official product, that is more suited to that particular application, the L-201 is not the cheap option for a comparison microscope, good as it is, it is not entirely suited to that application.

Support for GLOIC microscope range
The current range of GLOIC microscopes can be found at:

Their network of specialists are more than capable of ensuring despatch of completed orders, support, servicing and calibration of all of their products for Institutional and Academic use. Personal enquiries from individual end users will probably be redirected to smaller distributor specialists. And please don't forget that China is a massive place, and also a very great distance from Europe and the Atlantic, so if you approach Chinese vendors direct, don't be surprised to find that they will probably require a reasonable size order to make shipping the goods worthwhile (i.e. >£100, or $200.) China prefers US dollars for international trading.

GLOIC also offer a great range of accessories to complement their L range of microscopes. It is possible to obtain, digital cameras, software for PC, and all sorts of fixtures and fittings, polarizers and phase contrast sets, objectives, and measurement optics, to upgrade the L-201 for any functional use, with only one caveat, YOU ARE REQUIRED TO KNOW THE PRODUCT YOU WANT TO BUY and its Part reference before approaching any Chinese vendor, import export specialist, or optical distributor. If YOU get the order for the product wrong, that is not THEIR problem. As with any production base, the Factory supports its own product range, but refers small orders to distributors, so make use of the GLOIC site for reference to compatible parts and accessories, and don't waste their valuable time without an order.

Another useful associative reference for GLOIC instrumentation, was at Ningbo Yuda is at Ketty Wang for Yujie optical for professional, medical, hospital, educational and academic supplies of Optical equipment and the products that were listed on China Yutai site here. with a catalogue that was listed on the Ningbo Yuda catalogue at chinayutai but seems better available from their other site. Ningbo Yuda has a sister company that supplies commercial products for the consumer market called Ningbo Yujie and it is worth visiting their products page at Ninbo Yujie & Yuda Products for the general microscope page at General microscope product page, and the specific microscope place at L-201 microscope page, for the L-201 microscope specifications, and the Microscope accessories page, for information relating to their assembly version of the L-201 microscope, as some of the parts for this model, like the mirrors, are compatible with the GLOIC model.

International Distributor.

If you have never purchased direct from China before, the whole experience can be quite daunting. Individuals in the UK tend to think small, China is massive, and its production capacities are huge: obtaining parts from a number of different sources would tend to increase the shipping costs, so it is usually better to approach a specialist in the particular field who can collate the items together, deal with all the necessary payments and ship them to your locality.

Basically there are two options, you can approach a specialist in your host country, or you can approach a specialist in the country of manufacturing origin. If you have absolutely no clue what you need, and how to do business with China, then it is probably better to approach a specialist in your own country, but usually they will advise according to their current contact network of supplies.

Personally, this was not an option open to me: nobody in the Uk specialized in the GLOIC L-201 model or accessories for it. So I approached Mr J. Wu of L and W Optics Electronics Co., Ltd.

Mr Wu's company operates from a region very close to the GLOIC factory and so it was possible for him to receive and despatch an order as a GLOIC distributor. I found Mr Wu took care in every aspect of his service in ensuring all parts were exactly despatched to match my requirements.

When extending the magnification range of a microscope, by increasing the power of the lenses, it is important to ensure that the optics are matched to minimize further focusing adjustment. Because Mr Wu's company is familiar with the L-201, it was not a problem to match a high power 100x objective with the correct 35 mm parafocal length to match the existing set of lenses on the L-201. The company also collated parts from Yujie/Yuda and the GLOIC, and were able to supply a replacement mirror for the L-201. Jack Wu was accurate in every detail of my order and requirements and so I don't have a problem in personally recommending his company as being the experts they are for the product.

I have had personal contact and dealings with the following people and therefore can vouch them as honourable valuable and helpful in trading and assistance. Ketty Wang, Elys lv and Sam Fu in the Yujie company, and also Kevin at Guangzhou Liss Factory, and they are very helpful in general, and honourable people to deal with.

There seems to be a bit of confusion about the exact specifications of the microscopes originally got shipped over here, in the sense of a product down grade from the full specifications of the L-201, and L-201A, as originally sold by Yujie medical, in 2001. To clear up this confusion, I have managed to find two other sites of real interest, because they boast first the full specifications for the product, and second, the exact part number that distinquishes the industrial grade product from the educational grade product. The industrial grade product, is the product of most interest to our industries and medical teams, and also, our investigators, and researchers.

The industrial grade product, was, I am advised, sold by RS Components originally, albeit not present in their current catalogue, for what reason, I know not, but I guess, some fellow tried to palm them with toy microscopes, when they ordered real ones, and that disgrace, rests with our import people for misordering, and trying to spiff the customer funds. Maybe there was a product move forward in Japan, and RS were sourcing from that supplier source, unwitted that their microscopes were actually being made in China. I heard all the excuses of IT records on the phone: truth is they aint telling. So this is a link to a Japan tool making company called Hozan, they deal with microscopes for Printed Circuit inspection, and their range of numbers seem to correlate with the range of the form of numbers on the L-201 microscope. Hozan parts for newer microscopes but not now listing L-201. This company also has distributors in the USA IKAS Incoroporated and other distributors listed here Other Hozan distributors but the lack of a listing might explain why RS dont have that model in their catalogue at present.

So, where are we, through a list of sources that have and are known to have distributed the microscope at some point, much further onwards than obstructions and excuses offered for non support by Europe companies, that were ostensibly using ex stock write offs to support their own ranges. I have no evidence of Paralux France actually being a manufacturer of microscopes. Neither do I have evidence of Euromex Holland, manufacturing microscopes, I have made a genuine reference to their offering a diversity of L-201 products, that at some point did use or did supply the bonefide heavy product as it originally shipped.

So if you require a genuine, industrial microscope, from a known good source, and want the exact L-201 spec and can't speak French or understand the heavy accent of Chinese English, here is what I suggest.

Midwest USA GB type
Midwest USA GK type
Midwest China GB type L201
Midwest China GK type L201A

and expect to see this
GB type XSP91L201sq.gif
or this
GK type XSP91L201Arnd.gif


Lighting is an important part of microscopic study. Unless your expertise extends to fluorescent work, and necessitates the use of the Ultra Violet or Infra Red range, WHEREABOUTS SPECIAL SAFETY PRECAUTIONS ARE NECESSARY TO PROTECT EYES, and INDIRECT OBSERVATION IS BETTER THAN LOOKING DIRECTLY THROUGH THE MICROSCOPE LENSES, then you will probably be wanting to select decent illumination accessories to support your studies.

When selecting illumination for microscopy, you will be attempting to ensure that the light shown to the eye, and the specimen, peaks to a Zenith, about and around, the colour white you choose, and with spectral losses to a NADIR about the regions of black light radiance of Ultra Violet and Infra Red which damage the eye: but the problem is, white is not a colour, because it contains every colour of light in the spectrum.

Despite the existence of a Geneva convention which prohibits anyone from causing any kind of deliberate visual impairment, most people I have encountered in the UK are pig ignorant to Colour and Colourometry, and Eye Safety pertaining to Black radiance: even those practising in Optometry, and Optical transmissions, or under the spotlight of photography in the media, save for Tussaurd's in London, who expressly forbid any flash photography on their site. It is unacceptable practice to simply flash out the Hi Tones of eye sensitivity of the Public domain of the UK, simply because one or two large communication companies want to make use of an optical frequency for their optical communication networks, or mis-represent inaccurate, slow, java intensive search results, on the Internet, and force people to stare at screens, for longer periods of time, by obscuring information they require.

As white light contains all wavelengths of light, lamps are usually classified by their colour temperatures, rather than by the wavelength of light they produce. This is usually indicated in Kelvin, and is a measure indicative of the spectral tendency of white light towards the red or blue extreme of the spectrum. The colour temperature of normal daylight varies, according to the placement of the sun on the horizon, and the clarity of the atmospheric conditions of the day.

The most discriminating images through optical systems is achieved by a tendency towards the blue end of the visible spectrum, at the expense of the colour balance to red, people tend to speak of light peaking in this region as colder. But to ensure the visibility of all spectral components of a subject under study, it is also necessary to achieve an even spread of light upon the object. I am not about to make a suggestion about the best light to use for your particular area of interest, but by consulting specialist web sites it is possible to know the colour temperature of the light that best suits your need.

The traditional way of choosing a lamp is by using a colour chart standard:

It is also possible to calculate the colour temperature of white light directly as Mike Guidry reveals on his site:

Spectral emission of Light Emitting diodes is regulated by several standards which may be consulted for reference:

CIE/ISO Led Standards

  • CIE 127 LED measurement standard.
  • TC 2-45 Recommended geometries for luminous flux and intensity measurements on LEDs.
  • TC 2-46 Standards on LED Intensity Measurements.
  • TC 1-62 Colour Rendering of White LEDs.
  • TC 2-50 Measurements of LED clusters and arrays.

By using Mike Guidry's online Applet, I was able to easily derive that the spectral bandwidth of light in the visible spectrum ranged from 4100 degrees Kelvin at the red extreme, to 7100 degrees Kelvin at the blue end. Although one would readily expect White light to exist at around 6100 degrees Kelvin, in point of fact, the colour temperature best suited to achromatic lens systems, is achromatic light which nears the equilibrium of energy of spectral emissions at about 5000K.

Personally, I choose the LAI-1 (LAI and LED 1 cluster) from GLOIC, which consists of a switchable Annular LED illumination cluster (4424721), and a Power supply (4421511). This unit was supplied to me by GLOIC by Mr J. Wu of L and W Optics Electronics Co., Ltd. The unit offers ranges of light in Colour temperatures from 5000 Kelvin to 5500 Kelvin. It was originally designed to grant overhead lighting to the stage of a single lens optical microscope system by direct attachment to the microscope.

I did not consider electrical attachments to a microscope, a very good plan, but as the LAI-1 comes with clamps and a hole wide enough to be supported by a standard Radio Spares gooseneck microphone stem, it can be readily adjusted to present light from a variety of angles to anywhere about the microscope as a separate item.

The Power supply can be adjusted to switch light to a combination of rings, expanding and contracting the light source, and the intensity of light can be increased according to the task. Simply put, these GLOIC products are proving extremely useful, not only for microscopy but for other craft work too!


GLOIC LAI-1 LED 1 Cluster and PSU.

Further information.

Many people express interest in the character and quality of LED lighting in online news groups. Some expressed their perplexion to me as to the fitting of the LAI-1 to a student microscope.

While it is impossible to give an accurate representation of the frequency or wavelength of white light, as can be appreciated by the grasping that true white light is formed from radiants of all luminal spectra, it is possible to approximate the degree to which white light tends towards the infrared or the ultra violet blue areas. The LAI-1 is sited in spectrally in the centre of the visible spectrum, tending toward the blue slightly as the intensity adjustment is increased on the power supply. The spectra give a flat and even light, of daylight colour temperature, which is suited to the achromatic lens supplied from GLOIC, and well away from the red and blue area.


GLOIC LAI-1 LED 1 Cluster for the POS.

Of course the LED cluster light I have shown, is specifically designed to be fitted to a POS or polarised light microscope with interchangable objectives and not a rotating turret. This was not an oversight in my design concept, as I have already made mention of my intentions to fit the LAI-1 unit to a microphone gooseneck stem. I have found that a standard heavy cast iron base, and a 19 inch flexible gooseneck provides the greatest capacities for adjustments of either oblique overhead, or underside lighting from a mirror. A 12 inch goose neck is available but this is generally too short to be of serviceable value in the practical sense. Obtaining a Rubber bush is essential to the task, and these can be obtained from your local walking stick stockist. These rubber stoppers fit, exactly over the end of the gooses neck as shown.


Rubber Bush mounting on the gooseneck stem.
Lightbase.jpg      Goose.jpg
The Base and the gooses neck.

Fix the light cluster onto the lower end of a walking stick rubber and tighten the three screws to leave an impression mark on the peripheral regions of the rubber, and then remove it. With a hot iron, it is possible to make three small indentations at these marks so that when tightened the screws are affirmly fixed into the rubber. An additional hole can be created slightly nearer to the open end of the rubber, taking care to note that this is the correct (stem) side of the washer; and this will accommodate the throughput of the cable to stem centre, and onward to the power supply. If you are not familiar with using an iron to solder, and capable of re-affixing a plug to the lead after it has been threaded through the rubber, gooseneck, and base, then tacking the cable to the exterior stem of the goose, with a cable tie wrap, will be your best and perhaps your only option.

Once the cable is threaded through your preferred path, the hole in the side of the rubber, through the centre of the gooseneck and base to the power supply the plug can be resecured to the lead end. Alternatively gather the Cable tie wraps from the hardware store and affix the lead to the exterior of the gooses neck, for an truly unsightly piece of engineering craftwork. The walking stick rubber will now slide tightly over the gooseneck, and the LED cluster can be fixed to the stem by tightening the three screws ensuring the screws are correctly seated in the indentations you made at the start.

The application of glue between the gooseneck stem and the rubber bush is only an optional means of ensuring better security of the rubber to the gooseneck stem. The application of hot glue, from a hot glue gun is therefore an optional provision of security, but I have found I have achieved perfectly acceptable results without the use of glue and depending on a rubber alone.

Complete Assy.jpg

The completed assembly.

If things go right you should end up with a completed lamp assembly looking like this.

Final remarks.

Please always ensure you wear safety glasses or safety spectacles when using your microscope in class or at home. You might think that too sensible to mention but I have found the fool is always just one door away.

The BS Slide: Standards info for microscopy interfacing.

Best wishes
David Christmass



David Christmass
Mailing Address: Room 1, No 2, Victoria Road, Canterbury, Kent, UK. CT1 3SG.
©David Christmass 2013

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Published in the March 2010 edition of Micscape Magazine.

Major update March 2011: Lamps.

Major update February 2013: Improvements to information for service personages.

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