Rheinberg illumination is an optical staining technique for microscopic imaging. The light passing through special filters provides chromatism between the specimen and background, which improves the contrast of colorless and transparent samples effectively. Rheinberg illumination microscopy based on programmable liquid crystal display (LCD) replaces the condenser diaphragm of conventional microscope with low-cost thin film transistor liquid crystal display. By displaying different patterns, numerous microscopy imaging modalities, such as bright field, dark field, phase contrast, oblique illumination and Rheinberg illuminations can be realized. Furthermore, because it is easy to modulate both the color and the intensity of the LCD panel, the system derives completely new methods for optical staining, such as iridescent dark-field and iridescent phase-contrast imaging. The versatility and effectiveness of the system are demonstrated by microexamination of several transparent colorless specimens, such as unstained lung cancer cells, textile fibers, and slice of mouse kidney.