Preci-Lock/Preci-Beat
Preci-beat, a dedicated locking controller for Beat frequency locking/Beat phase locking, is also introduced to differential frequency outputting of the laser and phase difference locking for customs.
For integrated system or portable laser system, PreciLasers offers an integrated optical path or integrated stabilized modules. Frequency stabilization can be achieved by PC software with little laser power. Integrated optics modules connected in the form of full optical fiber are provided to help customers adapt to the more complex environment.
A fully functional laser locking controller (Preci-Lock) developed by Precilasers can be used for frequency locking in different application scenarios. Preci-Lock integrating modulation and demodulation module, PID module and high voltage amplifier module. It integrates the functions of error signal generation, PID servo and PZT drive. Preci-Lock can been used as locking controller for a variety of common frequency stabilization techniques, such as absorption spectrum, saturated absorption spectrum, modulation spectrum, modulation transfer spectrum and PDH technology.
The Preci-Lock controller mainly includes the modulation and the demodulation module, the PID module and the high voltage amplifier module. In addition, it also includes a RS422 protocol communication interface and a ±12V power supply interface. The preci-lock can be satisfied for most common requirements of laser frequency stabilization.
Parameters
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Indexes
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Modulation Power Range
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0-1023(Max. 10dBm)
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Modulation Output Frequency
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20MHz/3MHz/10kHz
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Phase Regulation Range
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0-360°
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PD Signal Input Range
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<1Vpp
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PD Signal Input Coupling
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AC Coupling
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PD Signal Input Coupling Impedance
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50 Ω
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The modulation and demodulation module modulate the laser, and demodulate the spectral signal detected by the detector to produce error signal. The modulation frequency can be customized according to customer.
Parameters
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Indexes
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Fast Output PID
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Single- Channel PIDP
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Slow Output PID
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PIDP+ PI Tandem
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PIDP Integral Folding Frequency
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(3.4 kHz-34 kHz) , (1 kHz-10 kHz) , (330 Hz-3.3 kHz) , (100 Hz-1 kHz) , (33 Hz-330 Hz) , (10 Hz-100 Hz) , (3.3 Hz-33 Hz) , (1 Hz-10 Hz)
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PIDP Differential Folding Frequency
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16 kHz , 34 kHz , 59 kHz , 133 kHz , 284 kHz , 483 kHz , 724 kHz
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PI Integral Folding Frequency
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33 kHz , 10 kHz , 3.3 kHz , 1 kHz , 330 Hz , 100 Hz , 33 Hz
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Fast Output
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Output Bandwidth
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500 kHz
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Output Range
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-9 V-9 V
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Bias tuning Range
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0-9 V
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Gain tuning Range
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0.0005-25
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Output reverse function
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Inclusion
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Slow Output
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Output Bandwidth
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500 kHz
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Output Ranges
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-9 V-9 V
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Bias tuning Range
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0-9 V
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Gain tuning Range
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0.0003-20
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Output reverse function
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Inclusion
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|
Scanning frequency
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2 Hz
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Scanning waveform
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Triangular Wave
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Maximum Scanning Range
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0-9 V
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Error signal bias adjustment
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Range
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-2 V- 2 V
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Accuracy
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0.25 mV
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Error Signal Input
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Unsaturated range
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-0.5 V-0.5 V
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Input Impedance
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51Ω
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Lock Reference Input
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Input Range
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-9 V-9 V
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Input Impedance
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1 MΩ
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The frequency of the laser can be controlled by PID module through feedback signal according to the error signal. PID module in Preci-lock is in series PID structure, including two PI, and offering two output ports, the parameters of the module can be adjusted with high precision.
Parameters
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Indexes
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magnification
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15
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Output Range
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0-110 V
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Bandwith
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High resistance load bandwidth 50 kHz
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Capacitive load bandwidth (small signal output (0.1 uF load) 20 kHz
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|
Drive Capability(Max. Output Current )
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50 mA
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Some lasers or devices require high dc voltage to drive the PZT. Preci-lock's built-in high dc voltage amplifier module can output a voltage signal of up to 110V with its 15 times amplification.
For a better laser frequency control, Preci-Lock abandons the physical knobs and buttons. And all parameter changes and locking control are realized by the PC software.
Preci-lock software includes the functions of communication control, reference and error signal display, PID module parameters adjustment, locking control and so on. Except the necessary physical connection, the laser locking control can be fully realized by Preci-Lock software. A pure digital operation is more convenient for user. Another feature of Preci-Lock software is the automatic locking function, which can realize the automatic locking of laser frequency under reasonable parameter settings. In automatic locking mode, Preci-Lock can realize auto locking, unlock judging and re-locking of the laser frequency. This mode can realize the long-term stable locking of laser frequency, especially suitable for the cold atom physics experiment that requires long-term continuous measurement.
As a fully functional locking control module, Preci-Lock can meet the most demands of frequency locking. The frequency locking can be divided into internal modulation and external modulation frequency locking according to the different modulation. The two frequency locking methods are different in principle while the physical connecting of Preci-Lock is also different for them.
For internal modulation, the modulation signal and feedback signal feedback together to the laser through an adder. The frequency lock point corresponding to the wave peak and wave trough of the spectra. Typical internal frequency stabilization modulation is adopted in lock-in saturation absorption spectrum or absorption spectrum frequency stabilization.
For external modulation, the modulation signal and feedback signal are divided and the external modulation signal is applied to an external independent modulator. The frequency lock point corresponding to the zero point of the spectra. Typical external frequency stabilization modulation is adopted in modulation transfer spectrum or PDH frequency stabilization.