1.The microscope rests securely on a stand on a table.

2.Daylight from the room (or from a bright lamp) shines in at the bottom.

3.The light rays hit an angledmirrorand change direction, traveling straight up toward the specimen. The mirror pivots. You can adjust it to capture more light and alter the brightness of the image you see.

4.The light rays pass through a hole in an adjustable horizontal platform called thestage.

5.The stage moves up and down when you turn a thumb wheel on the side of the microscope. By raising and lowering the stage, you move the lenses closer to or further away from the object you're examining, adjusting the focus of the image you see.

6.To look at something under a microscope (such as a plant leaf), you prepare a specimen of it. The specimen has to be a very thin slice so light rays will pass through.

7.You mount the specimen on a glassslidewith a glasscover slipon top to keep it in place.

8.The slide is held in place by two metal clips, one on either side.

9.Light traveling up from the mirror passes through the glass slide, specimen, and cover slip to theobjective lens(the one closest to the object). This makes the first magnification: it works by spreading out light rays from the specimen so they appear to come from a bigger object. The objective "lens" usually consists of more than one lens.

10.A selection of other objective lenses can be used to magnify the specimen by more or less.

11.The thumb wheel makes it easy to swing the other lenses into position.

12.Theeyepiece lens(the one closest to your eye) magnifies the image from the objective lens, rather like a magnifying glass.

13.On some microscopes, you can move the eyepiece up and down by turning a wheel. This gives you fine control or "fine tuning" of the focus.

14.You look down on a magnified image of the object.

Aborescope(occasionally called aboroscope, though this spelling is non-standard) is an optical device consisting of a rigid or flexible tube with aneyepieceon one end, anobjective lenson the other linked together by arelayoptical system in between. Theoptical systemin some instances is surrounded by optical fibers used for illumination of the remote object. An internal image of the illuminated object is formed by the objective lens andmagnifiedby the eyepiece which presents it to the viewer's eye.

Endoscope

Most of the telescopes you see today come in one of two flavors:The refractor telescope, which usesglasslenses.The reflector telescope, which uses mirrors instead of the lenses.Both types accomplish exactly the same thing, but in completelyTheobjective lens(in refractors) orprimary mirror(in reflectors) collects lots of light from a distant object and brings that light, or image, to a point orfocus.Aneyepiece lenstakes the bright light from the focus of the objective lens or primary mirror and "spreads it out" (magnifies it) to take up a large portion of the retina. This is the same principle that a magnifying glass (lens) uses; it takes a small image on the paper and spreads it out over the retina of your eye so that it looks big.

A telescope's ability to collect light is directly related to the diameter of the lens or mirror -- theaperture-- that is used to gather light. Generally, the larger the aperture, the more light the telescope collects and brings to focus, and the brighter the final image.