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1. Многозначность слов

A plate

Van Leeuwenhoek's microscopes consisted of a small, single converging lens mounted on a brass plate, with a screw mechanism to hold the sample or specimen to be examined.

The stage usually has arms to hold slides (rectangular glass plates with typical dimensions of 25×75 mm, on which the specimen is mounted).

2. Глаголы трудные для перевода

To allow

The arm angle may be adjustable to allow the viewing angle to be adjusted.

To be due to

Compound microscopes are heavier, larger and more expensive than simple microscopes due to the increased number of lenses used in construction.

It took about 150 years of optical development before the compound microscope was able to provide the same quality image as van Leeuwenhoek's simple microscopes, due to difficulties in configuring multiple lenses.

Due to the difficulty in preparing specimens and mounting them on slides, for children it's best to begin with prepared slides that are centered and focus easily regardless of the focus level used.

To produce

The Huygens ocular is still being produced to this day, but suffers from a small field size, and other minor problems.

Anton van Leeuwenhoek (1632–1723) is credited with bringing the microscope to the attention of biologists, even though simple magnifying lenses were already being produced in the 16th century.

To give

In some high performance microscopes, the optical configuration of the objective lens and eyepiece are matched to give the best possible optical performance.

Galileo's microscope was celebrated in the Accademia dei Lincei in 1624 and was the first such device to be given the name "microscope" a year later by fellow Lincean Giovanni Faber.

To provide

It took about 150 years of optical development before the compound microscope was able to provide the same quality image as van Leeuwenhoek's simple microscopes, due to difficulties in configuring multiple lenses.

The whole of the optical assembly is traditionally attached to a rigid arm which in turn is attached to a robust U shaped foot to provide the necessary rigidity.

3. Ложные друзья для переводчика

Actual

The actual power or magnification of a compound optical microscope is the product of the powers of the ocular (eyepiece) and the objective lens.

Actually

The date is unlikely, as it has been shown that Zacharias Janssen actually was born around 1590.

Commercial

The vast majority of modern research microscopes are compound microscopes while some cheaper commercial digital microscopes are simple single lens microscopes.

Instruments

Demonstrations by British microscopist have images from such basic instruments.

Van Leeuwenhoek's home-made microscopes were very small simple instruments, with a single, yet strong lens.

Material

These are used with index-matching material such as immersion oil or water and a matched cover slip between the objective lens and the sample.

The refractive index of the index-matching material is higher than air allowing the objective lens to have a larger numerical aperture (greater than 1) so that the light is transmitted from the specimen to the outer face of the objective lens with minimal refraction.

Objective

Some high performance objective lenses may require matched eyepieces to deliver the best optical performance.

Oil immersion objective

Some microscopes make use of oil-immersion objectives or water-immersion objectives for greater resolution at high magnification.

Originally

If a microscope did not originally have a mechanical stage it may be possible to add one.

Originally images were captured by photographic film but modern developments in CMOS and charge-coupled device (CCD) cameras allow the capture of digital images.

Specific

Modern biological microscopy depends heavily on the development of fluorescent probes for specific structures within a cell.

Since the mid 20th century chemical fluorescent stains, such as DAPI which binds to DNA, have been used to label specific structures within the cell.

Techniques

While basic microscope technology and optics have been available for over 400 years it is much more recently that techniques in sample illumination were developed to generate the high quality images seen today.

This method of sample illumination gives rise to extremely even lighting and overcomes many limitations of older techniques of sample illumination.

4. Наречия трудные для перевода

To be unlikely

The date is unlikely, as it has been shown that Zacharias Janssen actually was born around 1590.

5. Слова, близкие по написанию, но разные по значению

About, above

It took about 150 years of optical development before the compound microscope was able to provide the same quality image as van Leeuwenhoek's simple microscopes, due to difficulties in configuring multiple lenses. Still, despite widespread claims, van Leeuwenhoek is not the inventor of the microscope.

The former typically ranges from 5× to 100× while the latter ranges from 0.14 to 0.7, corresponding to focal lengths of about 40 to 2 mm, respectively.

To attack, to attach

The whole of the optical assembly is traditionally attached to a rigid arm which in turn is attached to a robust U shaped foot to provide the necessary rigidity.

To because, because of

Historically optical microscopes were easy to develop and are popular because they use visible light so the sample can be directly observed by eye.

Coarse, course, of course

Focus wheel to move the stage (4 – coarse adjustment, 5 – fine adjustment)

Adjustment wheels move the stage up and down with separate adjustment for coarse and fine focussing.

Normally this will include controls for focusing, typically a large knurled wheel to adjust coarse focus, together with a smaller knurled wheel to control fine focus.

Considerable, considered

Though now considered primitive, the use of a single, convex lens for viewing is still found in simple magnification devices, such as the magnifying glass, and the loupe.

Only, the only(+сущ.)

A simple microscope is a microscope that uses only one lens for magnification, and is the original design of light microscope.

Present, to present, to be present

Optical microscopes are the oldest design of microscope and were possibly designed in their present compound form in the 17th century.

To prove, to provide

It took about 150 years of optical development before the compound microscope was able to provide the same quality image as van Leeuwenhoek's simple microscopes, due to difficulties in configuring multiple lenses. Still, despite widespread claims, van Leeuwenhoek is not the inventor of the microscope.

The whole of the optical assembly is traditionally attached to a rigid arm which in turn is attached to a robust U shaped foot to provide the necessary rigidity.

Some, the same

Some microscopes make use of oil-immersion objectives or water-immersion objectives for greater resolution at high magnification.

The vast majority of modern research microscopes are compound microscopes while some cheaper commercial digital microscopes are simple single lens microscopes.

It took about 150 years of optical development before the compound microscope was able to provide the same quality image as van Leeuwenhoek's simple microscopes, due to difficulties in configuring multiple lenses. Still, despite widespread claims, van Leeuwenhoek is not the inventor of the microscope.

All modern optical microscopes designed for viewing samples by transmitted light share the same basic components of the light path, listed here in the order the light travels through them: In addition the vast majority of microscopes have the same 'structural' components.

The same controls enable the microscope to adjust to specimens of different thickness.

Feature, future, further

Other features may be lamp controls and/or controls for adjusting the condenser.

The condenser may also include other features, such as a diaphragm and/or filters, to manage the quality and intensity of the illumination.

Unable, to enable, value, volume

The same controls enable the microscope to adjust to specimens of different thickness. In older designs of microscopes, the focus adjustment wheels move the microscope tube up or down relative to the stand and had a fixed stage.

They were awkward in use, but enabled van Leeuwenhoek to see detailed images.

Typical magnification values for eyepieces include 2×, 5× and 10×.

A typical value of the enlargement factor is around 5× (for the case of 35mm film and a 15x10 cm (6×4 inch) print).