Linear CCD with Teensy 4.0 and Hyperspectral Imaging

DrM

Well-known member
This is a single board that hosts a linear CCD with analog front end and a Teensy 4.0. The analog section provides shift, invert and gain to match the full swing (dark to saturation) from the CCD to the input range of the 12 bit ADC of the Teensy 4.0, while isolating the gain section from part variances. The trim pot allows a finer though manual adjustment for the offset. The firmware provides ASCII controls and responses and binary or formatted data transfer, with clocked, triggered, or gated operation.

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Following is an example of a hyperspectral image recorded with the sensor using a graded bandpass filter for wavelength selection.

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Here is the full setup for the measurement, minus the lid on the chamber. Notice the Teensy 3.2 enabled data acqusition card, current amplifier (small square green pcb) and "Easy Driver" for the stepper motor above the T3 DAQ. (The perf board is a pulse stretcher that I threw together to conveniently monitor the shutter start, since then replaced with a pcb). The T3 DAQ was described here https://forum.pjrc.com/threads/53173-queued-USB-DAQ-with-the-Teensy.

The T3 DAQ generates the applied voltage pulse, triggers the T4 LCCD, records the current, operates the motors and records temperature using a thermistor. The DHT22 in the picture is a secondary temperature monitor, the primary thermistor is mounted close to the sample and is hidden from this view by the graded bandpass filter. The chamber is installed on top of a thermoelectric cooler and filled with Argon for the run. A python program controls and coordinates the T3 DAQ and T4 LCCD, displays the data in real time graphics, and adjusts power to the cooler as needed.

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