Teledyne 400E - Optical Bench

Model 400E Ozone Analyzer
Instruction Manual
THEORY OF OPERATION
P/N 04316 Rev: B 229
10.3.3. Optical Bench
Electronically, the Optical Bench is a group of subassemblies that emits UV Light of
the proper wavelength; passes it though a tube filled with Sample Gas; detects the
presence of UV radiation not absorbed by any O
3
present in that Sample Gas and
outputs a voltage signal proportional to the amount of UV detected.
Sample Gas Inlet
Optical Bench
Chassis
Sample Gas
Outlet
Absorption Tube
UV Lamp Heater
& Temperature
Sensor Assy,
UV Lamp
Sample Gas
Temperature
Sensor
UV Lamp
Power Supply
UV Detector
Preamp Assy
UV Detector
Housing
Figure 10-5: Optical Bench Layout – Top View
Photometer UV Lamp
A mercury-vapor UV lamp. This lamp is coated in a material that optically screens
the UV radiation output to remove the O
3
producing 185nm radiation. The majority
of the light emitted is at the 254nm wavelength.