Projectors used in projection clocks are similar to other projectors, and use the same optical principles.

This light emission is based on the nonlinear optical principle.

They are used to demonstrate basic optical principles.

Modern devices use ultrasound technology, while earlier models were based on optical principles.

The optical principles of multiview auto-stereoscopy have been known for over a century.

The two images are separated either laterally within the visual field or at different focal planes, as determined by the optical principles employed.

Simple optical principles combine the upside down scene outside the pinhole camera with the silhouettes of the objects inside the camera.

It employed radio signals rather than optical principles and produced on a viewing screen a close-up picture of the object being sighted.

Defects in vision can be explained using optical principles.

Cognitive illusions include some which result from the unconscious misapplication of certain optical principles.