DigiLock 110: Digital Locking
——Digital laser locking module
ØFPGA-based laser locking: Fast & flexible
ØFully digital and computer controlled
ØFast response, high bandwidth
ØMultiple PIDs, Lock In, Pound-Drever-Hall, FFT, network analysis
ØClick & Lock, Auto- & ReLock, response, simulation
TOPTICAs DigiLock 110 is the versatile solution for laser control, stabilization, characterization & analysis. Its digital nature makes it easy to use, flexible and intelligent. The FPGA based hardware allows for high bandwidth and flexibility, and with its clever software one has the overview, but can go into every tiny detail if need be.
The DigiLock 110 features multiple digital controllers. PID parameters, bandwidths, etc. can be digitally entered. The user can easily go back to well proven parameter sets and change parameters in well defined steps. With the parameters given, the DigiLock can calculate the controller frequency response in amplitude and phase and visualize it – a useful tool in optimizing locking performance, especially in conjunction with spectrum and network analysis.
The DigiLock 110 AutoLock feature controls multiple PIDs and the analog P simultaneously. It scans the laser to the desired lock point, and enables all PIDs at the right moment. The DigiLock can detect a correct lock through several means, allow a lock only under certain circumstances and try to relock in a well defined and controlled way once it does fall out of lock. This intelligence makes locking lasers a lot more comfortable and maximizes measurement time for the user.
The DigiLock 110 module supports the user in many ways. When optimizing laser locking parameters, it is useful to see, how the spectrum of the error signal looks like. The DigiLock can not only display time signals, but it can also display the spectrum of a signal. Oscillations can be easily detected and residual laser noise analyzed. Also, the frequency response of the actuators in the laser play an important role when choosing corner, modulation and filter frequencies. DigiLock offers network analysis functions for determining actuator bandwidth and resonance frequencies.
Functionality Overview
Functionality | Value | Unit | Comment |
Scan function | |||
Scan frequency | 0.1 Hz - 33 MHz | Bandwidth limited on some channels | |
Waveform types | Sine, triangle, square, sawtooth | ||
PID function 1 | |||
Signal latency | 200 | ns | ADC and DAC latency included |
Parameters | P, I, D, I cut-off | ||
PID function 2 | |||
Signal latency | 200 | ns | ADC and DAC latency included |
Parameters | P, I, D | ||
Analog P function | |||
Bandwidth | 21 MHz (-3 dB, -200° phase) | ||
Lock-In function | |||
Modulation frequency | 12 Hz - 781 kHz | ||
Pound-Drever-Hall function | |||
Modulation frequency | 1.56, 3.13, 6.25, 12.5, 25 | MHz |
Input Channels
Input Channels | Resolution | Sample rate | Bandwidth | Range | Impedance | Comment |
(bit) | (Hz) | (-3 dB) (Hz) | (V) | (Ohm) | ||
Main in | 14 | 100 M | 14 M | ± 2.1 | 50 | Input signal at has to be between ± 3.5V; it can be shifted with the and amplified with the PGA |
Aux in | 14 | 100 M | 15 M | ± 2.1 | 50 | |
Precise in | 16 | 200 k | 50 k | ± 2.0 | 10 k | |
DCC Iact | 16 | 100 k | 15 k | ± 13.1 | 40 k | SYS DC 110 backplane |
DTC Tact | 16 | 100 k | 15 k | ± 13.1 | 40 k | SYS DC 110 backplane |
AIO 1 in | 16 | 100 k | 15 k | ± 12.5 | 47 k | Normally used as output |
AIO 2 in | 16 | 100 k | 15 k | ± 12.5 | 47 k | |
Sum in | 27 M | ± 1.0 | 50 | Bandwidth between and |
Output Channels
Output Channels | Resolution | Sample rate | Bandwidth | Range | 50 Ohm | Comment |
(bit) | (Hz) | (-3 dB) (Hz) | (V) | driver | ||
Main out | 14 | 100 M | 19 M | ± 1.0 | Yes | Sum of and Analog P branch |
Aux out | 14 | 100 M | 19 M | ± 1.0 | Yes | |
SC 110 out | 21 | 100 k | 18 k | ± 6.5 | No | SYS DC 110 backplane; |
amplification by 15 with SC110 | ||||||
DCC Iset | 21 | 100 k | 18 k | ± 6.5 | No | SYS DC 110 backplane |
DTC Tset | 16 | 100 k | 18 k | ± 6.5 | No | SYS DC 110 backplane |
AIO 1 out | 16 | 100 k | 16 k | ± 6.5 | No | |
AIO 2 out | 16 | 100 k | 16 k | ± 6.5 | No | Normally used as input |
Error out | 20 M | ± 1.7 | Yes | Error out = (+ ) x Gain/2; bandwidth between and | ||
TRIG | 0, 2.6 | Yes |
General
General | Value |
Supply voltage | ± 15 V |
Supply current +15 V (typ) | 700 mA |
Supply current -15 V (typ) | 200 mA |
The DigiLock 110 module makes laser locking easy. Many supporting features help beginners and experts alike. After selecting a slope or peak in a spectrum, the software can trace this feature in consecutive scans of the laser. With a mouse click, the laser scans to the desired lock point and activates the lock, exactly where the user wants it.
The DigiLock 110 module offers both Lock-In and Pound-Drever-Hall techniques for top-of-fringe locking. Both techniques work with modulating/demodulating the laser frequency and the measured photo diode signal. The modulation frequencies are variable and reach up to 780 kHz for the Lock-In module and up to 25 MHz for the Pound-Drever-Hall module. These high modulation frequencies allow for a higher locking bandwidth and therefore a more stable lock.
Applications
ØAtom Laser Cooling & Trapping
ØIon Laser Cooling & Trapping
ØDegenerate Quantum Gases (BEC, DFG)
ØRydberg Excitation
ØOptical Pumping & EIT
ØQuantum Dots & Microcavities
ØSensing & Metrology
ØComputing & Simulation
ØSpectroscopy
ØFrequency Comb Spectroscopy
公司介绍
德国Toptica公司为科研及工业应用开发并制造激光系统，产品线包括二极管激光器，超快光纤激光，太赫兹系统以及频率梳等。TOPTICA激光器优良的性能表现，可靠性以及使用寿命收到各方OEM客户，科学家以及多位诺贝尔奖获得者的首肯。
