SRS Stanford Research Systems SR540 Optical Chopper Controller with 4 Hz to 3.7 kHz Range, 4-Digit Frequency Display and GPIB, RS-232, Ethernet Interfaces

The SR540 Optical Chopper Controller handles all your optical chopping requirements—from simple measurements to dual-beam and intermodulation experiments. Featuring a 4-digit frequency display, front-panel frequency control, analog voltage frequency control, and two reference outputs with selectable operating modes.

• Frequency range: 4 Hz to 3.7 kHz
• 4-digit frequency display with 1 Hz resolution and accuracy
• Front-panel frequency control with 10-turn potentiometer
• Analog voltage frequency control (0-10 VDC)
• Two reference outputs with multiple operating modes
• Includes two anodized aluminum blades: 5/6 slot and 25/30 slot

A single optical beam is chopped by either row of slots, with the corresponding reference output used to lock the lock-in amplifier to the chop frequency.

Output from a single source is split and chopped at two different frequencies. One beam passes through the experiment while the other serves as a reference beam, with signals detected at different frequencies for improved measurement accuracy.

• SR540 - Optical chopper
• O5402530 - 25/30 dual-slot replacement blade
• O54056 - 5/6 dual-slot replacement blade
• O5405 - 5-slot replacement blade
• O54030 - 30-slot replacement blade
• O540RCH - Replacement chopper head