Lamp Filament Alignment

This tutorial explores how the lamp filament is aligned by observing changes through a "virtual" diffusion screen inserted over the field diaphragm light port. Instructions about how to operate this tutorial appear under the applet window.

Lamp filament alignment in reflected light microscopy is also simulated in this tutorial, except that the virtual light port is substituted by the virtual eyepiece tube. Use the sliders to position the lamp filament for optimum intensity and position. The "Lamp Intensity" slider controls the voltage to the lamp filament, and should be positioned between 8.5 and 10 volts. Filament "focus" is achieved with a slider that allows the filament to drift into and out of focus. The "rotation" slider is used to compensate for slight rotations of the filament with respect to the microscope axis. Translation of the filament in both the X and Y directions is accomplished with the appropriate sliders. After the filament has been aligned, use the radio buttons to toggle a Bertrand lens into the viewfield to ensure the filament image completely fills the back focal plane of the objective. The virtual diffusion screen is placed on the light port for the purpose of aligning the filament and should be removed before examining or photographing specimens.