QCL500 Laboratory Series 500 mA QCL Driver Instrument

  • Output current of 500 mA
  • Low noise: <0.4 μA RMS up to 100 kHz
  • Adjustable compliance voltage: up to 20 V
  • Analog modulation up to 2-3 MHz
  • Constant Current Mode Operation
  • Intuitive touchscreen user interface
  • USB, Ethernet interfaces with software
  • Store data on computer or flash drive
  • 19" Rack mountable: 2 U and 1/2 rack
  • Maximum safety features for your QCL

From: $3,516.00

Bulk Pricing (6 - 14): $3411.00

Contact Factory for High Volume Pricing
Price adjustments will be reflected in the cart. For availability information please contact us. All prices are in US dollars and are subject to change without notice. Prices do not include shipping charges. An additional OEM discount applies on orders over 14 pieces. Contact factory for pricing. If ordering from or shipping to Australia, China, or Hong Kong, please contact your distributor.

These low noise QCL driver instruments have the lowest current noise density of any commercially available. They enable lower detection thresholds in gas, liquid, and material sensing systems. Powering a QCL with Wavelength’s patented1 driver gives you narrower linewidths, stable center wavelength, and repeatable scans.

This is the right instrument for lasers that require a high-precision and ultra-low noise current source to measure concentrations lower than ever before. The 500 mA QCL driver exhibits noise performance of 0.4 μA RMS to 100 kHz, and an average current noise density of 1 nA / √Hz.

To help you get the best performance from your QCL driver, Wavelength provides on-line Application and Technical notes:
AN-LD08: Manage Grounding to Minimize Noise with the QCL Drivers
AN-LD09: Troubleshooting Low Noise Systems
TN-LD02: How is Current Noise Measured at Wavelength Electronics

We are sure that once you experience the precision, stability and ease-of-use of our touchscreen instruments, you’ll be convinced that they are ideal for your high performance application. We are offering a test drive any instrument for 30 days for free.  Activate the test drive.


The QCL Driver family is available in four different instrument models so that you can choose the ideal one for your application:


In order to maintain a characteristically tight center linewidth and minimize jitter, quantum cascade lasers must be powered by drivers with exceptionally low current noise density. Our customers have reported achieving narrower linewidths with our QCL drivers than any other they’ve used.


The high modulation bandwidth and fast rise-time maintains modulation waveform integrity so you can shape the laser output profile exactly as your application requires.


With Wavelength’s plug and play instrument, controls are set quickly using either the instrument touchscreen or a remote computer, and results are easy to monitor. This allows taking your revolutionary QCL application from the test bench to market quickly and efficiently.

A LabVIEW Virtual Instrument application is available for remote operation. Complete installation and operation instructions can be found in the Virtual Instrument Operating Guide.

Remote operation is also possible using the USB and Ethernet Test and Measurement Class Command Set. Complete installation and operation instructions can be found in the LAB Series Command Set document. If you are using the QCL LAB with firmware version 0.79 or earlier, it is remotely controlled using Wavelength’s QuickConnect Application (QCA):

You can upgrade the firmware for free to use the Command Set or VI here. If you are upgrading from version 0.79 to version 1.5+, all calibration and user data will be converted and saved. If you downgrade from version 1.5+ to version 0.79, all existing calibration data will be lost.


All the essential control and monitor functions expected in a Wavelength product are incorporated into this QCL driver, along with protection circuitry to safeguard the QCL from minor power source faults, over-temperature conditions, and electrical faults.

The soft-clamping current limit can be set without enabling the driver output, and uses a brick-wall never-exceed limit circuit to protect the QCL from potentially damaging overcurrent situations. Additionally, the QCL instrument comes standard with many other safety features:

  • Power supply over current protection
  • Brown-out and overvoltage protection
  • Driver over-temperature protection circuit
  • Relay shorts output when current is disabled
  • AC input and patented power supply filtering
  • Key switch, active, and passive interlocks
  • Password protection available to lock out a selectable control set.
  • 2 second turn-on delay
  • 1.5 msec current ramp

An Interlock Kit, which includes a BNC terminator and modified D-SUB connector to override interlocks, is included with the instrument. Single and dual rack mount kits are available. Windows-based software also comes with the instrument.

A rack mount temperature control instrument, the TC LAB Series, is available:
TC10 LAB 10A Controller
TC15 LAB 15A Controller


Once you have finalized your work, the QCL circuitry is available in compact OEM versions:


Due to their unique construction, QCLs operate with high power in the near-IR through terahertz ranges. These wavelengths are particularly suited to detection of molecules significant to humans.

Applications for the lower noise QCL driver include: remote detection of explosive materials, medical diagnosis using the breath, non-invasive glucose testing, emissions monitoring of the atmosphere or marine environments, and pharmaceutical process quality control. Additional applications include anesthesia and hospital air quality monitoring, leak detection, remote imaging, and cavity ring-down spectroscopy.

1Covered by U.S. Patents 6,696,887; 6,867,644 and 7,176,755. Licensed from Battelle Memorial Institute.

Free, effective, and responsive technical support is available to simplify integration of Wavelength products into your OEM design. Standard product can be easily modified to meet your application requirements.

Dimensions: 3.5 x 8.9 x 17.7 inches (89 x 226 x 450 mm)
Supply Range: 115 / 230 ±15% VAC, Switch selectable: 110-120 V and 220-240 V
Output Current: 500 mA
Compliance Voltage: up to 20 V (The unit will only deliver the voltage that the load requires, up to the compliance voltage limit.)
Long-term Current Stability at ambient 25°C: typically 10 ppm
Temperature Coefficient: typically 10 ppm
RMS noise 1 Hz to 100 kHz: typically 0.4 µA
Competitor Noise Comparison
Average Current Noise Density: 1 nA / √Hz
Noise Characterization Scan: Spectral Noise Scans are available from 1 Hz – 100 kHz. Request at time of purchase.
Bandwidth: 2 – 3 MHz (CC). Bandwidth will depend on QCL impedance and wire lengths.
Rise / Fall times: 250 nsec (to full scale) / 200 nsec

QCL Instrument Specification Comparison Chart

* Citations for the QCL Series:

Quick Start Wiring Diagram
qcl lab wiring218

Instrument Control Screen
control screen218

Instrument Limit Screen
limit screen218

LabVIEW Virtual Instrument Settings & Monitor Screen

LabVIEW Virtual Instrument VI Scan Screen – Scan of Resistive Test Load
vi scan218


QCLTL-LOQCL Test Load for QCL500 & QCL1000$100
INTLK REPL KITQCL Lab Series Interlock Replacement Kit$35
RCKMT-LABSNGLLaboratory Series Single Unit Instrument Rack Mount Kit$135
RCKMT-LABDUALLaboratory Series Dual Unit Instrument Rack Mount Kit$135
55-110014SMA to BNC Cable$45
55-1100153-foot Male-Male USB Cable$19
WCB310WCB310 SMA to SMA Cable, 36”, male-to-male$28

Related Parts

QCL1000 LABQCL1000 Laboratory Series 1 A QCL Driver Instrument$3648
QCL1500 LABQCL1500 Laboratory Series 1.5 A QCL Driver Instrument$3778
QCL2000 LABQCL2000 Laboratory Series 2 A QCL Driver Instrument$3916
QCL500 OEMQCL500 OEM Low Noise 500 mA Quantum Cascade Laser Driver$1696qcl500-oem