Optical Lenses
The compound light microscope is equipped with two types of lenses:
- Eyepiece Lens: This is the lens through which the user views the specimen. Its magnification power typically ranges from 5 to 30 times, though it is often set to magnify at 10 or 15 times.
- Objective Lenses: A compound microscope features three to four objective lenses that magnify the specimen between 4 and 100 times.
Illumination Source
The compound light microscope incorporates a light source, allowing the user to observe the specimen effectively. This illumination source may consist of an electric lamp or a light-emitting diode (LED), coupled with a condenser and a diaphragm. These components work together to gather and focus light on the specimen, typically located beneath the stage.
Stage
The microscope is fitted with a component called the stage, where the slide containing the specimen is placed. The stage typically includes clips, which serve to secure the slide in position. If the stage is fixed, the clips will remain stationary; however, in the case of a mechanical stage, the clips can move, allowing the user to shift the slide during examination.
Adjustment Knobs
The compound light microscope includes movable adjustment knobs if it possesses a mechanical stage. Their primary function is to raise or lower the stage to achieve a clear view of the specimen. These include the coarse adjustment knob and the fine adjustment knob. The coarse adjustment knob is used with lower power objective lenses (4x to 10x) since its movement causes significant displacement of the stage, which could potentially damage the specimen if higher magnifications are employed. Conversely, the fine adjustment knob is meant for making slight adjustments during the use of higher power objective lenses (40x and 100x) to enhance the clarity of the view.
Other Components
The compound light microscope comprises several additional components, including:
- Eyepiece Tube: This tube connects the eyepiece lens to the objective lenses.
- Microscope Arm: This part connects the body tube to the base and is utilized for handling the microscope.
- Microscope Base: The fundamental support of the microscope, which typically houses the illumination source.
- Nosepiece: A rotating part of the microscope that allows users to switch between different objective lenses.
- Rack Stop: A disk designed to prevent the user from moving the objective lenses too close to the slide, thus avoiding breakage.