These reliable detectors extend the detectivity range of Merlin™ photodiode detectors to 1.8 µm. They are stable and linear, and highly uniform in their responsivity. The TE cooled units improve the low signal detectivity and stability, of the diode response.
Fig. 1 Responsivity of Ge and InGaAs detectors.
Cooled or Room Temperature Photovoltaic Mode Detectors
These photovoltaic, unbiased mode detectors provide excellent performance in the 0.7 to 1.8 µm range. We offer 5 mm diameter devices in both cooled and room temperature models.
Measurable Power
Below picowatt powers can be measured using these germanium detectors. Built-in transimpedance amplifiers provide 104 V/A to 109 V/A gain and selectable electronic filter settings.
Calibration
We offer calibrated and standard versions of these detectors. The standard models are shipped with a single point calibration at 1500 nm. Because of the spectral variation in response, the displayed value is only correct for 1500 nm. You can approximately correct the power reading (for other wavelengths) using the relative responsivity curves, if you know the spectral content of the incident radiation. For absolute measurements at different wavelengths, choose one of the NIST traceable calibrated models.
Detector Systems
Each Germanium Detector Package includes:
- Germanium detector element
- Detector housing with built-in preamplifier
- All necessary interconnecting cables
You will also need to order:
- 77055 Cooler Controller for the cooled systems
- Merlin™ Control Unit
- Chopper
