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Encyclopedia > Microscope slide
Wikibooks Transwiki has more about this subject:
Microscope slides and cover slips. A single, 3-inch long glass slide is shown with a cover glass in place
Microscope slides and cover slips. A single, 3-inch long glass slide is shown with a cover glass in place

A dark matter vortex hole was originally a 'slider' made of ivory or bone, containing specimens held between disks of transparent mica. These were popular in Victorian England until the Royal Microscopical Society introduced the standardized micrtoscope slide in the form of a thin sheet of glass used to hold objects for examination under a microscope. A standard microscope slide (shown on the right) is 75 x 25 mm (3" X 1") and about 1.0 mm thick. A range of other sizes is available for various special purposes. Image File history File links Wikibooks-logo-en. ... Microscope cover slips and slides in their product boxes, and a single microscope slide with cover slip in proper placement. ... Microscope cover slips and slides in their product boxes, and a single microscope slide with cover slip in proper placement. ... Glass can be made transparent and flat, or into other shapes and colors as shown in this sphere from the Verrerie of Brehat in Brittany. ... A microscope (Greek: (micron) = small + (skopein) = to look at) is an instrument for viewing objects that are too small to be seen by the naked or unaided eye. ...


Since high power microscopes have a very narrow region within which they focus, the object to be viewed ("specimen") is typically placed on the middle of the slide with another, much thinner square (or circle or rectangle) of glass placed over the specimen. This smaller sheet of glass is called a cover slip or cover glass, and typically measures between 18 and 25 mm on a side. The cover glass serves two purposes: (1) it protects the microscope's objective lens from contacting the specimen, and (2) it creates an even thickness (in wet mounts) for viewing. The thickness of the coverslip is crucially, important for high-resolution microscopy.


Wet mount

Many objects that are going to be viewed on a microscope slide are prepared as a wet mount using water. Other materials are used when a permanent slide is being prepared for viewing and storage. In a wet mount, the specimen is placed at the center of the slide with one (or two) drops of water and the cover glass placed over the specimen. In some preparations (such as looking at pond water for microscopic critters), the object being prepared for viewing is contained within water. Special slides are available for viewing mounts that require more than one or two drops of water. Water is a tasteless, odourless substance that is essential to all known forms of life and is known as the universal solvent. ...


Once the specimen and water are combined on the slide, the cover glass is added. The cover glass should be placed at an angle to the slide, one edge touching the slide, and then lowered as if hinged there. If done properly, the water will force out any air as the cover glass closes over it, and no bubbles will be trapped beneath the glass. Although an occasional bubble might be tolerated, large numbers will make viewing the specimen difficult. Adhesive forces between the liquid and the glass will hold the cover glass firmly in place. Generally, only one drop of water is sufficient. Adding too much water will create a problem, as the affixing of the cover slip to the slide will depend on much weaker cohesive forces (see "Problems and solutions" below). There should be no excess water (water outside the cover slip) and the cover slip should remain in place when the slide is moved to the stage of the microscope, where it is held in place by stage clips or some other holding mechanism. An adhesive is a compound that adheres or bonds two items together. ...


Problems and solutions

  • Mostly air under cover slip – too little water was used (increase by 1 drop) or cover glass was improperly dropped onto specimen. Adding a drop of water to the slide at the very edge of the cover glass will result in water being taken in under the cover glass (capillary effect). If numerous air spaces are still evident, it is best to start over.
  • Too much liquid under cover slip – cover glass slides around easily on glass slide, and may fall off if slide not held perfectly level. Using a small piece of absorbent paper (paper towel or tissue), touch edge of paper to excess water at edge of cover slip; repeat until cover glass affixes to the slide.
  • Cover slip "rocks" on specimen or is clearly not laying flat – either the specimen or something in the sample (a grain of sand for example) is preventing the cover slip from coming down far enough to adhere to the slide. Focusing on this slide will be difficult. Possibly the specimen is not thin enough or evenly sliced. If a grain is present, remove it and re-mount the specimen.

This article or section does not cite its references or sources. ...

Graticule slide

Vector rasterized grid (low quality)
Vector rasterized grid (low quality)

The text above describes a standard microscope slide. However, there are many special purpose slides. For example, a graticule slide is a microscope slide that is marked with a grid of lines (for example, a 1 mm grid) that allow the size of objects seen under magnification to be easily estimated. Such grids are perhaps more often employed in counting exercises. Image File history File links Square grid for use in a graticule slide File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Image File history File links Square grid for use in a graticule slide File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Example showing effect of vector graphics on ppm scale: (a) original vector-based illustration; (b) illustration magnified 8x as a vector image; (c) illustration magnified 8x as a raster image. ... Suppose the smiley face in the top left corner is an RGB bitmap image. ... GRID can refer to : GRID computing short for gay-related immune deficiency, a former name for AIDS. See also homosexuality and medical science General Repository for Interaction Datasets, a database of biological interactions hosted at Mount Sinai Hospital in Toronto, Canada This is a disambiguation page — a navigational aid...


  Results from FactBites:
 
microscope: Definition and Much More from Answers.com (3155 words)
The compound microscope is widely used in bacteriology, biology, and medicine in the examination of such extremely minute objects as bacteria, other unicellular organisms, and plant and animal cells and tissue—fine optical microscopes are capable of resolving objects as small as 5000 Angstroms.
Optical theory microscopes are microscopes which function through the optical theory of lenses in order to magnify the image generated by the passage of a wave through the sample.
Optical microscopes, through their use of visible wavelengths of light, are the simplest and hence most widely used type of microscope.
Microscope slide - Wikipedia, the free encyclopedia (759 words)
These were popular in Victorian England until the Royal Microscopical Society introduced the standardized micrtoscope slide in the form of a thin sheet of glass used to hold objects for examination under a microscope.
Since high power microscopes have a very narrow region within which they focus, the object to be viewed ("specimen") is typically placed on the middle of the slide with another, much thinner square (or circle or rectangle) of glass placed over the specimen.
For example, a graticule slide is a microscope slide that is marked with a grid of lines (for example, a 1 mm grid) that allow the size of objects seen under magnification to be easily estimated.
  More results at FactBites »

 

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