HeNe

1
Spectrometer
L2
L3
L4
M3
L1 5cm diameter, 40 cm focus length L2 7.5 cm
diameter, 15 cm focus length L3 7.5 cm diameter,
20 cm focus length L4 5 cm diameter, -7.5 cm
focus length L3 and L4 will match spectrometer
NA L3 and L4 can be replaced by a 7.5 cm
diameter, 50 cm focus length lens with NA
mismatched. (Need 60 cm focus length but no
product available) L1 AR coating for 350-650,
650-1050 L2,L3,L4 AR coating for 650-1050,
1050-1650
L1
Chopper
Ge detector
LD
M2
Flip mirror
HeNe
M1
1. Fill LN2 to the detector, wait 1 hour 2. Use
the switch key to turn on the HeNe laser 3.
Adjust detector bias to 250 V 4. Open the chopper
and the lock-in amplifier 5. When finished, turn
the switch key of the laser off 6. Turn off other
equipments
Mirror sets
2
Spectrometer
4
3
33 mW
1
32 mW
Chopper
2
Ge detector
31 mW
3
2
4
28 mW
LD
HeNe
1
HeNe laser power calibration
3
Spectrometer
3
2
62 mW
1
56 mW
Chopper
2
Ge detector
48 mW
3
ILD 100 mA
1
HeNe
780nm LD power calibration