Optical time delay control device

An optical time delay control device for controllably altering the transit time of an optical beam traveling through the device, the optical beam having a wavelength in a range from 1 to 2.5 microns and a transit time of the optical beam is controllably alterable by greater than about 1 nanosecond, the device comprising:

• an optically transparent solid medium for receiving the optical beam, the optically transparent solid medium having an optical absorption coefficient of less than about 10−3 cm−1, wherein at least a portion of the medium is generally a parallelepiped shape characterized by a height, length and width, wherein the length is larger than the height;
• two mirrors affixed to two opposing surfaces of the optically transparent solid medium, so that during operation the optical beam reflects between the two mirrors as the optical beam travels through the optically transparent medium;
• and
• an angle actuator for controllably altering the angle at which the optical beam enters into the optically transparent medium from a first angle to at least a second angle, thereby controllably altering a number of reflections between the two mirrors and thereby controllably altering the time for the optical beam to travel through the optically transparent solid medium from a first transit time to a second transit time, such that the difference between the first and second transit times is greater than about 1 nanosecond.