Specifications

Structure of Laser Unit (AOM)

Laser

0-th order light

AOM

• AOM controls the strength of laser light.

• The diffracted light of first order is used for exposure.

Exposure

100 %

80 %

20 %

2210

The direct light is called 0-th order light.

Diffracted light of

first order

33_2

Explanation

• When the voltage is not turned ON to AOM, the incoming laser beam passes through as it is.(0-

th order light)

• When turning ON the high frequency voltage, the ultrasonic waves occurs, and the diffracted

light which is separated from 0-th order light occurs.(Diffracted light of first order)

• Change the rate of 0-th order light and the diffracted light of first order by changing the high

frequency voltage on AOM, and control the strength of light (diffracted light of first order) to

be used for exposure.