High Power Precision Laser Diode Testing

Each LDX-36000 Series Laser Diode Driver was designed as a current source specifically for high power laser diodes. Ideal for R&D or manufacturing testing, precision low noise current control with set point accuracy of 0.1% of reading is delivered to the lasers, with four-wire voltage measurement and a photodiode monitor with adjustable reverse bias for CW and QCW LIV testing, laser qualification testing, or pulse testing.

Precision Pulse Control for High Power Laser Testing

The LDX-36000 Series offer several QCW operating modes delivering clean pulses with low overshoot and fast rise and fall times. Digital control of pulse width, duty cycle and frequency provide quick and easy control of pulse parameters for maximum fl exibility in varying test applications. The pulsed output can be generated in one of three modes; internal pulse, hard pulse, and triggered pulse. If the LDX-36000 is being used in diode-pumped solid state laser and amplifi er testing, programmable input and output trigger delays allow for optimizing Q-switch timing and energy extraction without the need for any external delay generators.

Choice of Laser Current Control Modes

Each LDX-36000 can be operated at full scale current and voltage in CW or QCW mode saving time and reducing cost of test by eliminating multiple instruments and test set-ups. Conduct CW L-I-V testing and pulse testing of high power laser diodes all at the same test station, without moving the laser or changing the output cable. With the 36000’s there is no need for another QCW instrument, simply change operating modes from the front panel or through the GPIB interface, set up the test parameters and start testing quickly in either mode. In QCW mode, the pulse output can be generated either internally with programmable pulse width, duty cycle and frequency parameters or through an external pulse trigger. For some applications, long pulse widths are required during testing. All 36000 models offer a "hard" pulse mode where the pulse width can be adjusted from 1 ms to 2 seconds with a duty cycle up to 90%. Additionally, a unique power display mode allows laser diode power to be set based on programmable slope efficiency and threshold current parameters.

Designed to Protect High Power Laser Diodes

Eliminate problematic current spiking common with voltage sources. Each LDX-36000 Series Laser Diode Driver was designed as a current source specifi cally for high power laser diodes. The drivers provide multiple laser diode protection features such as current and voltage limits, slow start turn-on, fl oating outputs, fast error detection, and immunity to operational and power line transients. Careful attention to design has resulted in minimal overshoot in QCW mode or while rapidly stepping current in CW mode at any output current level. Transients from normal instrument operation such as output on/off have been thoroughly tested and minimized as well as transients from inadvertent instrument operation (such as mode switching). In case of a device failure with multiple devices connected in series, low overshoot and closed-loop power supply control ensure the remaining devices safety. A temperature monitor provides additional protection with a programmable temperature limit which disables the current source output in a limit condition.

Automate High Power Laser Testing

Remote instrument operation is available on all of the LDX-36000 Series High Power Drivers through an IEEE488/GPIB interface. All instrument controls and functions are accessible through the interface for easy remote programming and control in automated test systems where repeatable and accurate test sequencing, measurements, and data handling are required. Whether the application is data intensive L-I-V testing, pulsed control for thermal characterization, or R&D evaluations, remote operation of the LDX-36000’s saves time and ensures systematic data collection and instrument operation.

Precision L-I-V Testing

Each LDX-36000 Series Laser Diode Driver was developed specifically for precision L-I-V testing of high power laser diodes with 0.1% set point accuracy, low noise and precision forward voltage measurement capability in CW or QCW pulsed modes. Additionally, the instrument can perform power measurements through an independent photo-diode input calibrated with a user-programmable responsivity. An adjustable 0 to -15V reverse bias ensures linear measurements and fast conversion speed. Accurate forward voltage measurements even with high current and long cable lengths are accomplished real time through a four wire measurement system. Reduce total system cost with these high current drivers; there is no need for separate pulsed sources, voltage measuring instruments, or low current measuring instruments for high power L-I-V. testing.

Ease of Operation

Designed for ease of use and readability, the front panel features dual 7-segment LED displays with instrument controls grouped by mode and function. The dual display lets you view laser parameters simultaneously with the bright 7-segment LED display highly visible from a distance in darkened labs. Parameters such as output current setpoint, current and voltage limits and calibration constants are easily selected and adjusted with the rotary digital encoder. Each display is easily configured to indicate laser parameters such as current, voltage, power, and temperature with discrete control push buttons located below each display. System errors such as open circuits and current or voltage limits are indicated with discrete LED’s with an error code indicated on the appropriate seven-segment LED display.

Save and Recall Instrument Settings

For multiple instrument test configurations, the LDX-36000 Series Laser Diode Drivers offer a SAVE and RECALL feature. The SAVE function allows you to store all the front panel settings for any given instrument configuration to a numbered bin. The RECALL function allows you to retrieve any of the saved configurations at any time through simple front panel button presses or remotely through the GPIB interface. This saves time in instrument re-configuration for different manufacturing runs or R&D experiments.