Figure 2.5 Wavelength Setting; Diverging Beams (Laser Diodes); Collimated Beams; Focused Beams - ILX Lightwave OMH-6727B User Manual

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C H A P T E R

Diverging Beams (Laser Diodes)

To accurately measure the power of diverging beams, the entire beam must enter
the measurement head aperture. The 6727B has been constructed so that the
laser diode packages may be placed very close to the entrance aperture.

Collimated Beams

Collimated beams must also fully enter the measurement head in order to
accurately measure optical power. With many lasers, radiation on the periphery of
the beam can change the power reading. However, placing the measurement
head extremely close to the laser can couple spurious light (such as fluorescence
or heat) into the head. A one meter distance between the source and the
measurement head is suggested.

Focused Beams

The OMH-6727B also accepts converging beams. In high power applications be
sure that the focus of the beam does not occur at the rear of the integrating
sphere. Again, perpendicular beam entry to the Head is required.

Fiber Optic Cable

A fiber optic adapter (options AO271, AO272, AO273, and AO276,) can be
mounted onto the face of the OMH-6727B Measurement Head. This threaded
ring/adapter cap option accepts a variety of fiber optic connector styles for direct
coupling of a fiber optic cable to the head.

Measuring or Setting the Wavelength

For automatic wavelength compensation of power measurements, press the
WAVELENGTH AUTO button so that the indicator above the button is lighted. The
wavelength of the source can also be manually programmed into the OMM-6810B
using the procedure below.
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OMH-6727B
O P E R A T I O N
General Operating Procedures

Figure 2.5 Wavelength Setting