Optical Chopper - SR540

Sum & difference reference outputs Bolt clamp or rod mounting 4 Hz to 3.7 kHz range Single & dual beam experiments Sum & difference outputs 4 Hz to 3.7 kHz chopping frequencies Single and dual beam experiments SR540 Optical Chopper The SR540 chopper will handle all your optical chopping requirements—from simple measurements to dual-beam and intermodulation experiments. The SR540 has a 4-digit frequency display, front-panel frequency control, analog voltage frequency control and two reference outputs with selectable operating modes. 25/30 Slot Blade Drawing 5/6 Slot Blade Drawing Base Plate Drawing SR540 Volatility Statement Chopper Experiments SR542 Precision Chopper SR865A Lock-In Amplifier SR830 Lock-In Amplifier SR2124 Lock-In Amplifier SR860 Lock-In Amplifier 25/30 Slot Blade Dwg. 5/6 Slot Blade Dwg. Base Plate Drawing SR540 Volatility Statement Chopper Experiments SR542 Precision Chopper SR865A Lock-In Amp. SR830 Lock-In Amp. SR2124 Lock-In Amp. SR860 Lock-In Amp. Single-Beam Experiment X Single-Beam Experiment SR540 Optical Chopper Single-Beam Experiment The SR540 chopper will handle all your optical chopping requirements—from simple measurements to dual-beam and intermodulation experiments. The SR540 has a 4-digit frequency display, front-panel frequency control, analog voltage frequency control and two reference outputs with selectable operating modes. Two anodized aluminum blades are provided: a 5/6 slot blade for frequencies up to 400 Hz, and a 25/30 slot blade for frequencies up to 3.7 kHz. Reference outputs are provided for frequencies corresponding to each row of slots, as well as the sum and difference frequencies. Optical Chopper Applications In this application, a single optical beam is chopped by the outer row of slots, and the reference output from the right BNC is used to lock the lock-in amplifier to the chop frequency. The inner row of slots could also be used, in which case the left BNC would be the reference output. In either case, the REFERENCE MODE switch is in the “up” position. Dual-Beam Experiment Dual-Beam Experiment X Dual-Beam Experiment SR540 Optical Chopper In this arrangement, the output from a single source is split and chopped at two different frequencies by the two rows of chopper slots. One beam passes through the experiment while the other is used as a reference beam. The beams are recombined and sent to the same detector. Two lock-ins are used to detect the signals at ƒ inner , corresponding to the experimental signal, and ƒ outer , corresponding to the reference beam. If the detected signal in the experimental arm is ratioed to the detected signal in the control arm, then effects due to changing source intensity and detector efficiency are removed. SR540 Specifications 4 Hz to 400 Hz (5/6 slot blade) 400 Hz to 3.7 kHz (25/30 slot blade) <2 %, 100 Hz < f < 3700 Hz 0.2° (50 Hz to 400 Hz) 0.5° (400 Hz to 3.7 kHz) 4-digit, 1 Hz resolution and accuracy 10-turn pot with 3 ranges: 4 Hz to 40 Hz 40 Hz to 400 Hz 400 Hz to 3.7 kHz Input control voltage 0 to 10 VDC for 0 to 100% of full scale. Control voltage overrides frequency dial. ƒ inner , ƒ outer , 5 × ƒ outer , ƒ inner + ƒ outer , ƒ outer - ƒ inner Controller: 7.7" × 1.8" × 5.1" (WHL) Chopper head: 2.8" × 2.1" × 1.0" (WHL) 12 W, 100/120/220/240 VAC, 50/60 Hz One year parts and labor on defects in materials and workmanship, 90 days on motor.