![]() Microscopes in most microbiology laboratories have three objective lenses: the low power objective lens (10X), the high-dry objective lens (40X) and the oil-immersion objective lens (100X). The magnifying power of an objective lens is engraved in the lens mount. In the compound light microscope two lenses, one near the stage called the objective lens and another in the eyepiece, enlarge the sample. Magnification increases the apparent size of an object. Light then passes up through the slide and into the objective lens where the first magnification of the image takes place. ![]() The condenser also collects the broad bundle of light produced by the light source and focuses it on the small area of the specimen that is under observation. (located in the condenser), regulates the amount of light reaching the specimen. As the magnification of the objective lens increases, more light is needed. The condenser serves two purposes it regulates the amount of light reaching the specimen and it focuses the light coming from the light source. The light from the illuminating source is passed through the substage condenser. If reflected illumination is used, a separate lamp provides a focused beam of light which is reflected upward through the condenser lenses by a mirror. A tungsten filament lamp usually serves as the source of illumination. Proper illumination is essential for effective use of a microscope. Light then passes through a series of glass prisms and mirrors, eventually entering the eyepiece (5) where is it further magnified, finally reacing the eye.įirst let us consider a primary feature of all microscopes, the light source. The light then enters the objective lens (4) and the image is magnified. Light, originating in the light source (1), is focused by the condensor (2) onto the specimin (3). Modern microscopes are complex precision instruments.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |