Fit The Focus Of The Lens To Show The Specimen In The Slide

Distance between objective lens and slide stage.

Fit the focus of the lens to show the specimen in the slide. In this figure light from the microscope illumination source passes through the condenser aperture diaphragm located at the base of the condenser and is concentrated by internal lens elements which then project light through the specimen in parallel bundles from every azimuth the size and numerical aperture of the light cone is. Make certain the condenser front lens does not contact the slide or push it up away from the stage. Do not allow the objective lens to touch the slide. When you want to study a slide under the microscope you place it on the.

When the specimen is focussed under low power move the slide so that what you want to see is dead center in your field of view then switch to a higher power objective. The focal plane is so narrow that it is very easy to focus right past it. By using a condenser lens you will increase both the illumination and resolution. A lens mounted in or below the stage.

Set the condenser height so that the front lens is approximately 1 to 3 millimeters beneath the lower surface of the specimen slide. This means the coarse focus knob must be used very carefully and slowly not to push it into the slide break the coverslip or squash your specimen. To focus on objects at these ranges you must use cover glass which is a paper thin piece of glass or plastic that is placed over the specimen. Focus carefully preferably by observing the lens itself while bringing it as close to the cover slip as possible then focusing by moving the lens away from the specimen.

What focus knob should you first use to bring a specimen into focus when using the scanning lens. Once you are using a high power objective focus using the fine focus knob only. The 40x and 100x objectives cannot focus on a specimen that is under a slide. When the 10x objective lens is in place the distance between the lens and slide is much smaller than when the lower objective usually 4x is in place.

A simple two lens abbe condenser is illustrated in figure 1. Fine focus knob. Do not let the objective lens touch the slide. The proper way to use a monocular microscope is to look through the eyepiece with one eye and keep the other eye open this helps avoid eye strain.

In extreme cases driving the condenser into the specimen will result in the sample being ejected from the. When viewing professionally made prepared slides make sure the specimen is face up cover glass on top when viewing. The higher power objective lenses have very tiny diameters and require concentrated light to work properly. You might need to readjust the sample into focus and or readjust the condenser and light intensity.

If you cannot focus on your specimen repeat steps 4 through 7 with the higher power objective lens in place. The purpose of the condenser lens is to focus or condense the light onto the specimen. If you cannot focus on your specimen repeat steps 3 through 5 with the higher power objective lens in place.