In light microscopy, lower magnification objective lenses are further from the specimen and survey a larger area, meaning more light enters the microscope, explains How Stuff Works. More magnification means the lens is closer to the stage, which also means less light enters the microscope, making the field of view dimmer.Know More
A light microscope works by shining a light up through objects, such as cells, on a slide. The light passes through the objects up into a small, spherical objective lens, up through the body of the microscope, through a second lens and finally into the eye of the microscope user. By this time, the image on the slide has been magnified many times.
Most light microscopes have a variety of lenses that allow a user to see objects under different magnifications. Each lens is a different magnification and a different distance from the stage. Lower magnification lenses are further from the stage, meaning they observe a larger area and allow in more light. Higher magnification lenses are much closer to the stage. In fact, at the highest resolutions, the lens is separated from the specimen by just a thin layer of oil. Since the lens is so close, the user sees a much smaller area, and less light enters the microscope and the eye. The differing amounts of light reaching the eye make the field of view brighter or dimmer.Learn more about Optics & Waves
A diaphragm on a microscope is the piece that enables the user to adjust the amount of light that is focused under the specimen being observed. A diaphragm is typically found on higher-power microscopes versus less expensive or toy models.Full Answer >
A compound microscope can be used to observe or analyze microscopic objects or organisms that may otherwise be too small for the naked human eye to accurately observe. Compound microscopes differ from common light microscopes and stereoscopes in their design and overall function.Full Answer >
A light microscope can use multiple types of light to produce multiple types of images, but all of them function on the basis of light focused from below the sample and into either a condenser, which focuses the light, or the lens to be viewed. The objective lens are what causes the actual magnification of the specimen on the slide that is made visible by the light. That is then passed through to the eyepiece at the top of the microscope.Full Answer >
In microscopy, the depth of field refers to the range of distance that runs parallel to the optical axis where the specimen can move and still be viewed without negatively affecting the clarity of the object under observation. The depth of field determines the vertical extent of the plane of focus, which is typically measured in microns.Full Answer >