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PPPPHARMACOGNOSY MICROSCOPE Lab 1 By Dr. Rusul.y hameed microscope instrument that produces enlarged images of small objects, allowing the observer an very close view of minute structures at a measure convenient for examination and analysis. An image m...

PPPPHARMACOGNOSY MICROSCOPE Lab 1 By Dr. Rusul.y hameed microscope instrument that produces enlarged images of small objects, allowing the observer an very close view of minute structures at a measure convenient for examination and analysis. An image may also be enlarged by many other wave forms,including audio, X- ray, or electron beam, and be received by direct or digital imaging or by a combination of these methods. The microscope may provide a dynamic image (as with conventional optical instruments) or one that is static (as with conventional scanning electron microscopes). TYPES OF MICROSCOPE Simple Microscope A simple microscope is defined as the type of microscope that uses a single lens for the enlargement of the sample. A simple microscope is a convex lens with a small focal length.  Compound Microscope A compound microscope is defined as the type of microscope that has more than one lens. It has a combination of lenses and two optical parts known as an objective lens and an eyepiece or ocular lens. Essential parts (main parts) of microscope: 1. Base (foot): a. give the stability to the microscope. b. hold the light source. 2. Handle (stand): hold all the enlarging lenses (ocular + objective lenses). 3. Stage: a. fixed stage. / b. mechanical stage Functions;- a. site of the slide which is fixed by using clips. b. containing opening which allows to light to pass from the light source toward the sample. c. move the slide forward, backward, right and left. 4. Condenser: focus the light that comes from light source toward the sample. 5. Auxiliary lenses: project a cane of light from light source toward the sample. 6. Iris diaphragm: give the optimum light. 7. Observation tube: hold the enlarging lenses (optical compounds). 8. Revolving nose piece: a. contain 4 holes in which the objective lenses are fitted. b. allows to switch from one power to another. 9. Objective lenses: enlarge the object and display the image toward the ocular lenses. Types;- 4X/10X/40X/100X (oil immersion lens). 10. Ocular lenses: enlarge the object and display the image toward the Ex;- 7X/10X / 20X... etc. Total magnification power = object power X ocular power. 11. Focusing mechanism: a. rough adjustment. b. fine adjustment.