Brightfield Microscopy Laboratory Operations Review 37
TERM EXPLANATION
Achromatic objective
Aperture diaphragm
Binocular microscope
Blue filter
Brightfield microscope
Compound microscope
Condenser
Depth of focus
Field diaphragm
Field of view
Immersion oil
Kohler illumination
Least expensive objective. Partially corrects for chromatic & spherical aberrations.Controls angle & amount of light sent to objective.One with 2 oculars.Used to eliminate yellow color emitted by tungsten.Uses transmitted light & lenses. Objects appear dark against white background. Used for most routine
clinical work.One with 2 lens systems—objectives & oculars.Focuses light on specimen.Distance throughout which all parts of specimen are in focus simultaneously.Limits area of illumination to image field.Area of specimen that can be seen.Used to help objective gather light from a wide numerical aperture. Provides high resolution. Type B (high
viscosity) is commonly used.Method of focusing & centering light path & spreading light uniformly. Ensures optimum contrast & resolution.continued...