Description |
The mode structure in a laser arises because of the periodicity conditions imposed by the cavity. The properties of a laser are drastically changed when an intracavity frequency-shifter is implemented, which changes the frequency of the light, circulation in the cavity at each round trip by an amount unequal to the free spectral range. The result is a comb of modes, with the comb components separated by the frequency shift per round trip. When such a laser is injected seeded with a phase modulated narrow band laser, a non-trivial scheme for laser ranging can be derived. This scheme will be demonstrated. Characteristic features depend on the gain medium used (fiber systems or solid state devices) and are: (i) measurement accuracy over order-of-meter distances of the order or a few micron with data acquisition rates of the order of 1 kHz or (ii) measurement accuracy over order-of-10-meter distances of about 100 micron with order of 1 MHz data acquisition rates. |
Organised by | Dr. Vaibhav Prabhudesai |