7711 New Focus Fizeau Wavelength Meter

The Newport / New Focus 7711 Fizeau Wavelength Meter can be used as a wavelength monitor for any tunable laser including dye, Ti:Sapphire or OPO systems. This easy-to use instrument has no moving parts, a minimum of optical elements and requires no internal reference calibration. A built-in microprocessor means the user won't need an additional computer to run it.

The simplicity of a Fizeau interferometer, in conjunction with the integrating effects of a CCD array, allows the user to measure the wavelength of both pulsed and cw light sources from 400 nm to 1.0 µm with 0.001-nm resolution. Because of the integrating effects of the CCD array, the wavelength meter is insensitive to pulse width. For repetition rates greater than 10 Hz, the wavelength meter is free running. For rates less than 10 Hz, the user will need to externally synchronize their laser to it.

To make alignment easy, a visible guide beam and a proportional numeric display of the CCD array signal has been manufactured. Simply align the user's signal to the guide beam and optimize coupling by consulting the front-panel display.

The user won't have to worry about output power fluctuations as the user is tuning their laser - even when the output signal varies by two orders of magnitude. This is because the wavelength meter includes automatic-gain control and the detector signal is automatically adjusted for optimum performance. The sensitivity of the CCD array allows measurements to be made with very low input powers.

While the wavelength meter is designed to measure single-frequency sources, broadband or multimode sources can also be measured. An external trigger input allows the user to synchronize with pulsed sources, or to sample at regular intervals. Wavelength can be displayed in either length (in air or vacuum) or frequency units. There's a delta mode which displays the difference between the current wavelength and a stored reference value and there's a wavelength hold for storing the current wavelength.