precaution while using microscope

MAKE SURE THAT THE 10X OBJECTIVE IS IN POSITION OVER THE VIEWING AREA. THE OBJECTIVE SHOULD BE POSITIONED ABOUT 1/4 3/8 ABOVE THE SLIDE. Glass knives, razor blades and scalpel knives are still sharp after being used. Discard only in containers provided for that purpose, or well sealed, and labeled cardboard boxes, so cleaning personnel will no be injured.

FOCUS ON SPECIMEN, FIRST USING THE COARSE AND THEN THE FINE FOCUS CONTROLS. YOU MAY HAVE TO MOVE THE SLIDE AROUND ON THE STAGE OF THE MICROSCOPE TO BRING THE SPECIMEN INTO THE VIEWING AREA. Microscopy is the technical field of using microscopes to view samples and objects that cannot be seen with the unaided eye (objects that are not within the resolution range of the normal eye). There are three well known branches of microscopy: optical, electron, and scanning probe microscopy.

USING THE CONDENSER FOCUS ADJUSTMENT KNOB THAT IS LOCATED ON THE LEFT SIDE OF YOUR MICROSCOPE JUST BELOW THE STAGE, MOVE THE CONDENSER UP TOWARD THE STAGE AS FAR AS IT WILL GO. Optical and electron microscopy involve the diffraction, reflection, or refraction of electromagnetic radiation/electron beams interacting with the specimen, and the subsequent collection of this scattered radiation or another signal in order to create an image. This process may be carried out by wide field irradiation of the sample (for example standard light microscopy and transmission electron microscopy) or by scanning of a fine beam over the sample (for example confocal laser scanning microscopy and scanning electron microscopy).

ONCE THE SLIDE IS IN FOCUS, IT MAY BE MOVED AROUND ON THE STAGE. AS LONG AS THE DISTANCE MOVED IS NOT TOO LARGE, THE OIL DROPLET WILL REMAIN BETWEEN THE 100X OBJECTIVE AND THE SLIDE. YOU WILL NOTICE THAT WHEN THE SLIDE IS MOVED, IT WILL BE NECESSARY TO RE FOCUS THE 100X OBJECTIVE USING THE FINE FOCUS CONTROL. AT VERY HIGH MAGNIFICATIONS, VERY SMALL CHANGES IN THE DISTANCE BETWEEN THE SLIDE AND THE OBJECTIVE WILL CAUSE THE IMAGE TO GO OUT OF FOCUS. IRREGULARITIES ON THE SLIDE AND ON THE STAGE OF THE MICROSCOPE ARE LARGE ENOUGH TO CAUSE CHANGES IN FOCUS.

Ergonomics is concerned with finding a better fit between people and the things they do, the objects they use, and the environmental setting in which they live, work, travel, and play. Also called human engineering, it is a relatively new branch of science that was founded in 1949, spurned by the development of new technologies during World War II. Throughout this period, it had become clear that, in order to be used safely and effectively, new technologies and products would need to account for human and environmental factors.

A regional survey of cytotechnologists (heavy users of microscopes) found that slightly over 70 percent reported having neck, shoulder, or upper back symptoms, while 56 percent had an increased incidence of hand and wrist symptoms. Other studies have revealed that approximately 80 percent of microscopists in all fields have experienced job related musculoskeletal pain and that 20 percent have missed work because of medical problems related to microscope use. The rather high 5 to 10 year dropout rate for cytotechnologists is attributed, in part, to physical discomfort associated with long hours examining specimens through the microscope. A majority of reported problems occur with the neck, back, shoulders, and arms, but there is also a percentage of microscopists reporting discomfort with their eyes.

Eye fatigue can be a major problem for microscope operators, especially if they have poor vision resulting from near or far sightedness, or astigmatism. If you are a beginning microscopist, you may tend to tense up when viewing. You think you have to set your eyes for near vision because, after all, you want to view something small. This is not the correct attitude in microscopy and may cause you strain in the long run. There is an easy remedy: First, look into the distance with your eyes relaxed and then into the eyepieces without changing the setting of your eyes. Only then should you set the interpupillary distance of the eyepieces via the folding bridge until you see only one circle instead of two. Remember to consciously use both your eyes for viewing.

The diopter adjustment provided on most microscope eyepieces can be used to compensate for minor focus problems, but microscopists who have moderate to severe astigmatism should wear glasses when viewing specimens through the eyepieces. In order to accommodate the longer eye point necessary for observation with eyeglasses, manufacturers offer specialized high eye point eyepieces. Users who do not wear eyeglasses should also keep this distance to permit the entire light from the microscope to find its way to the iris of the eye (Figure 2). If you slowly move your head back and forth in front of the eyepieces, you will soon find the optimum, relaxed posture that will allow you to see the entire circle of the field of view. If you do not wear glasses, the optional rubber cups on the eyepieces will be useful to you. They not only protect the eye from ambient light, but also help to keep the correct distance between the eye and the eyepiece.

Eyeglass wearers requiring simple lenses with a spherical power can use the microscope with or without their glasses, provided that the diopter setting of the focusing eyepiece is sufficient. However, if you require lenses with a toric power, for example lenses that refract light differently in the horizontal and vertical then you should wear your glasses for microscopy, since your eye has unsymmetrical aberrations that cannot be compensated by the diopter setting alone. This is how you test your glasses: view a simple geometric figure, such as a circle or a square, through the glasses you have removed from your eyes (see Figure 3). First you hold the glasses horizontally (Figure 3(a), then vertically (Figure 3(b) and 3(c)). If the figure appears compressed or expanded by this rotation about 90 degrees (Figure 3(b)), you will know that you are wearing lenses with a toric or another non spherical power.

If the rules listed above are followed, eyestrain will be minimized when peering into the microscope eyepieces with relaxed eyes (similar to observing a subject at a large distance). Many of the eyestrain problems that develop during extended periods of microscope use can be alleviated by employing video camera systems that display the specimen on a computer monitor. Without reading glasses, however, one has to accommodate to see the image clearly on t he monitor. Future microscope designs may eliminate the eyepieces altogether, substituting instead a CCD or CMOS image sensor for the classical observation tubes. The digital imaging chip will be coupled to a sophisticated software analysis package that controls image capture and storage, digital processing, and other features such as time lapse cinemicrography and real time video movies.