FAQs

Here we have answered some frequently asked question, if you can't find what you're looking for, get in touch by calling [phone number] or email us: enquiries@meijitechno.co.uk

Pricing is available through your local authorised Meiji Techno Microscope dealer. To find a dealer in your area, call us on [phone number] or contact us via enquiries@meijitechno.co.uk

Meiji Techno products are designed to deliver many years of trouble free use even in harsh industrial environments. Customer maintenance should be limited to simple cleaning of the outer surfaces of the microscope with water and a mild detergent and occasionally cleaning the outer surfaces of the lens with a commercially available lens cleaning solution. Never use hydrocarbon or alkaline-based solvents or concentrated alcohol solutions to clean your microscope. Any other repair or maintenance should only be performed by an authorised Meiji Techno repair facility.

Our Limited Lifetime Warranty, the consistent quality of our products. Patented designs. Meiji’s network of over trained dealers.

All Meiji Techno Microscopes have always been and continue to be manufactured ONLY in Japan.

Subject to normal use, all Meiji Techno Products are warranted for lifetime against defects in materials and workmanship. Damage resulting from use or repair by unauthorised parties or damage resulting from accident, alteration, misuse or abuse is not covered. The warranty gives you specific legal rights.

You may call us on [phone number] and describe the problem that you are having with your microscope. We can often determine over the phone whether it sounds like a warranty situation. If we are not able over the phone to make a determination, the next step would be to send your unit to us. When the technician inspects it upon arrival, he will determine whether it is a warranty repair or not.

 

You will then be notified so that you may approve the repair. If we get an approval from you, the technician will go ahead with the repair. Warranty repairs will be shipped back to you by courier with freight prepaid. If there is a charge for repair, it will be shipped back at the customer’s expense. All warranty repairs must be handled by our UK offices in Axbridge.

We charge £60.00 per hour for labour, plus parts & return shipping costs. Meiji Techno also has a large network of dealers around the country that offer local on-site service or will take your scope to their shop and return it to you within a reasonable period of time. Price quotes for such repairs are at the discretion of each individual dealer.

 

Meiji Techno is not responsible and will not be held to blame for any and all published or non-published documents for errors, for any damage to any product or products as the result of end users or Meiji Techno employees and their distributors and contractors in the use of any equipment or documents pertaining to the use or repair of applicable products and services.

A compound microscope has one optical path that is split at the observation tube that gives identical left and right images. A stereo microscope is like two compound microscopes side-by-side but with an offset from one another to mimic the natural offset of two eyes. It is the offset that provides depth perception in ordinary life and for the three-dimensional view or “erect image” in stereo microscopes.

Resolving power refers to the clarity with which an objective can clearly separate two points or lines lying close together. The shorter the distance between the points or lines, the greater the resolving power. Also the higher the N.A. (numerical aperture) number of the objective, the greater it’s resolving power. Resolution is the ability to distinguish two points as two points. One may need to compromise between resolving power and resolution to achieve the desired image.

The higher the N.A. value, for a given magnification, the brighter the image. A higher magnification reduces the brightness of an image.

The height difference within features of an object that appear acceptably sharp when viewed with an optical instrument. Depth of field depends on the objectives, eyepieces and tube factor. Depth of field decreases when increasing magnification.

Dioptric correction is the compensation of long- or short-sightedness by the adjustment of the eyepieces.

Light rays from all points in the field of view converge together at this point. This is where the user’s eye must be positioned.

The field number is the diameter of the eyepiece lens usually expressed in millimetres.

Field of View or FOV, is the amount of the object that can be seen with a particular optics combination. It is the circular area, which can be seen when looking into a microscope. It is combination of objective and eyepiece characteristics and field of view decreases with increasing magnification.

Interpupillary Distance is the distance between the centres of the pupils of your two eyes.

A stereo microscope can be said to be “parfocal” when an object can be observed from the lowest magnification to the highest without having to re-focus.

The working distance is the distance from the object plane to the front of the objective. Working distance decreases each time a higher-power objective is used.

The total magnification a microscope configuration is calculated from the magnifying power of the objective multiplied by the magnification of the eyepiece and, if installed, multiplied by the auxiliary lens.

Useful magnification is obtained when the magnification is between 500 and 1000 times the numerical aperture of the objective. Since the human eye has limited resolving power, the magnification should be selected so that the image details can still be distinguished by the eye. If the magnification falls below this range, details can no longer be recognized by the eye. If the magnification is above this range, this is simply referred to as “empty magnification” as the objective is no longer able to resolve structures. The image therefore appears out of focus.

The resolving power of an objective lens depends on its numerical aperture, which in turn depends on the refractive index of the medium between the specimen and the objective lens. A higher refractive index means the lens can gather more light and deliver a better image intensity. Air has a relatively low refractive index, and when it is the medium between specimen and the lens, lower N.A. objectives perform at their best capacity.

 

Higher N.A. objectives need a higher refractive index to operate and immersion oil provides that higher index. For optimum performance, you will also need to oil the top lens of the condenser to the bottom of the specimen slide. Immersion objectives are marked ‘oil’ or ‘oel’. Objectives marked ‘wi’, require water as the immersion contact medium.

In order to preserve darkness of the background for darkfield microscopy, the objective cannot have an N.A. higher than the lowest N.A. marked on the darkfield condenser. An iris that can reduce an objective’s N.A., can allow you to use higher N.A. objectives for darkfield work. Objectives with an N.A. above 1.2 require an iris for darkfield. For ordinary brightfield observation, the iris can simply stay wide open.

In most cases, from a transmitted light observation, you will only need a darkfield stop in the condenser. At higher magnifications, you will need an objective with an iris as well as a darkfield condenser.

The ‘0.17’ refers to the thickness in millimetres of the cover glass that was assumed by the lens designer in computing the corrections for the objective. For objectives with a numerical aperture higher than 0.45, departing from this thickness (or using no cover glass at all) may result in a less than satisfactory image.

The 160 identifies a finite tube-length objective, with a distance of 160mm from the nosepiece (where the objective screws in) to the top of the observation tube (where the eyepiece inserts). When you lengthen this distance by inserting accessories in the light path above the nosepiece, spherical aberrations will occur unless the accessories include the proper optical corrections.

With an infinity-corrected objective, light rays emerge in parallel projected toward infinity. Such an objective requires a tube lens in the light path to converge the parallel rays so that they come into focus at the eyepiece diaphragm.

A plan objective projects a flat image of the entire field of view.

With standard colours for most manufacturers, these rings make it easy to identify the magnification of the objective:

  • A red ring means 4X or 5X.
  • A yellow ring means 10X.
  • A green ring means 20X.
  • A blue ring means 40X, 50X or 60X.
  • A white ring means 100X.

These letters identify long or ultra-long working distance objectives where the working distance is much longer than standard objectives of similar magnification.

These letters designate an objective designed especially for use in Nomarski or differential interference microscopy. Meiji does not currently offer either method.

These objectives will have a very short working distance. To protect your microscope objective and your specimen, a spring-loaded front lens assembly retracts upon gentle contact with the stage or specimen. The retractable lens will not, however, protect against rough and continuous contact also known as “crashing” the objective.

The specimen may have a thicker cover glass than the standard 0.17mm, or you may have a thicker than normal glass slide. To improve the image, you might try using a dry objective with a correction collar, or you can try using 40X or 50X ‘oil immersion’ objectives, since the immersion objective has less sensitivity to variations in cover glass thickness.

Yes. Just move the phase condenser to the brightfield or “empty” position and employ the standard Koehler illumination procedure.

No, because the finite system does not include a tube lens to focus parallel rays.

Microscope objectives do not include correction for lateral chromatic aberration and require a compensating eyepiece (labeled ‘C’ or ‘K’) to provide correction. ‘WF’ signifies ‘widefield,’ meaning you can see more of the specimen at a given time. ‘H’ signifies ‘high eyepoint,’ which means you don’t have to put your eyes so close to the eyepiece during observation. These are typically meant for users who wear eyeglasses but anyone can use them.

Used for photomicrography rather than observation, a photo-eyepiece picks up the image delivered by the objective and projects it onto the film plane inside the camera. Photo-eyepieces usually come with low magnification power to lessen the chance of empty magnification when the images they project onto film are magnified.

To maintain useful magnification with satisfactory clarity and resolution, you must avoid empty magnification or making the specimen appear bigger but not clearer. In general, total magnification should not exceed 750X-1000X the N.A. of the objective. For example, with a 40X, N.A. 0.65 objective, the total magnification should be between 480X and 650X.

Neutral density filters absorb light evenly across the visible spectrum, thus lowering the intensity of light without changing its colour temperature.

A ‘daylight blue’ filter absorbs some of the yellow to red light from the microscope lamp, resulting in coloration much closer to natural daylight, which is beneficial comfortable viewing.

Use of a daylight blue filter is intended for observation purposes only, providing a pleasant background to the field of view. Do not use this filter for photomicrography or with daylight colour film.

Human eyes see the colour green the best. And, since monochromatic light eliminates chromatic aberration, a green filter markedly improves the performance of achromats. In addition, phase contrast objectives give their best images with green light.

Objectives are corrected for field curvature and colour aberration. The difference between Achromats and Plan Achromats is the degree of the flatness of field. When the image is in focus from the center towards its edges; the field is said to be ‘flat’. In general, the flatter the field of an objective, the more lenses it contains and the more expensive the cost.

‘DIN’ is an abbreviation of ‘Deutsche Industrial Normen.’ This is a German standard that has been adopted internationally as an optical standard used in most quality microscopes. The focal tube length of a DIN objective is 160mm. The former standard was RMS (‘Royal Microscope Society’), which had a longer tube length (170mm). Most DIN optics can be interchangeable. However, DIN and RMS objectives are not interchangeable.

A number usually engraved on an eyepiece, which refers to the diameter of a baffle or raised ring inside the eyepiece. The ‘FN’ of “field number” determines the viewing field for the eyepiece.

Proper illumination is critical to obtain a good image through any microscope so this topic deserves some time to research. Meiji Techno offers several options from which to choose. Whatever your specimen may be, Meiji has the appropriate illumination source to help to produce the best image possible.

Incandescent – Standard bulb filament, usually 6 -120V, 20 – 60W. Colour temperature is ‘warm’ and tends to look yellow.

 

Halogen – Usually low voltage, cooler, more intense illumination. Temperature is ideal for colour photography.

 

Fluorescent – A ‘cool’ system, which produces more light and has longer bulb life than incandescent bulbs. Fluorescent illumination offers a more desirable colour temperature (4100º Kelvin) with a ‘whiter’ field of view and is more comfortable to the eyes.

Coaxial refers to the movement of coincident axes or gears that share one common axis. On the coaxial controls of a graduated mechanical stage, one knob controls the ‘X axis’ movement and the other controls the ‘Y axis’ movement. On a coaxial focusing system the fine focus control is inside of the coarse focus control.

Darkfield Microscopy is a method by which the specimen (transparent or semi-transparent) is seen as a bright object against a dark, usually black, background.

Brightfield is perhaps the most common type of microscopy found in schools, industry and medical fields. In brightfield microscopy, a transparent or translucent specimen either naturally coloured or stained appears dark against a bright background or field.

A technique for revealing the structural features of microscopic transparent objects that cannot otherwise be accomplished with brightfield microscopy. Phase appears to achieve the same effect as staining a specimen (which would kill a live specimen).

Oil immersion is used with high power objective lens (usually 100X) as a medium between the lens and the cover slip. Because oil has the same light transmitting properties as glass, it cuts down the refraction of light rays. Other requirements include the use of a 1.25 Abbe condenser to be used.

A mechanical stage can be added to most Meiji Microscope models.

Yes. Video cameras, as long as they are the common ‘C-mount’ type, can be used with most Meiji Microscope models.

Yes, with a universal adapter and “T-Mount” matched to your camera brand and model.

Blurred images are usually the result of a dirty, scratched or broken objective. ‘Black spots’ are dirt particles in the eyepiece or dirt particles on head prism or mirrors. The following method works on them all:

 

The front lens of the objectives (particularly the 40X) should be cleaned after use by first brushing with a soft camel-hair brush to remove particles of dust, then by wiping gently with soft lens tissue, moistened with clean distilled water and drying with clean lens paper immediately following. The objective should never be taken apart except by a qualified repair person. If dust is seen on the back lens of the objective, an all-rubber ear syringe or enema tube may be utilized to blow the dust out.

 

The eyepiece may be cleaned in the same manner as the objectives. In most instances breathing on the lens to moisten it, then wiping dry with clean lens tissue will be sufficient to clean the surface.

 

The finish of Meiji microscopes is hard epoxy and is resistant to acids and reagents. Clean this surface with a damp cloth and mild detergent.

 

Note: Use alcohol for difficult cleaning and as a last resort Xylene or Acetone. Be forewarned that use of these chemical cleaners will destroy lens coatings!

 

If the problem requires more than a simple cleaning, your Meiji Techno Representative can refer you to an experienced microscope service dealer in your area.