DigiLock 110: Digital Locking
——Digital laser locking module
?FPGA-based laser locking: Fast & flexible
?Fully digital and computer controlled
?Fast response, high bandwidth
?Multiple PIDs, Lock In, Pound-Drever-Hall, FFT, network analysis
?Click & 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
?Atom Laser Cooling & Trapping
?Ion Laser Cooling & Trapping
?Degenerate Quantum Gases (BEC, DFG)
?Rydberg Excitation
?Optical Pumping & EIT
?Quantum Dots & Microcavities
?Sensing & Metrology
?Computing & Simulation
?Spectroscopy
?Frequency Comb Spectroscopy
公司介紹
德國Toptica公司為科研及工業應用開發并制造激光系統，產品線包括二極管激光器，超快光纖激光，太赫茲系統以及頻率梳等。TOPTICA激光器優良的性能表現，可靠性以及使用壽命收到各方OEM客戶，科學家以及多位諾貝爾獎獲得者的首肯。
