LAB-positioner-tilt

Scripts and codes for performing the positioner tilt test

Tilt Test Live Viewer

The script ui/liveview.py implements a live Gaussian spot tracker for the positioner tilt test setup. Acquires frames from a Thorlabs CS126MU camera, fits a 2-D Gaussian to the spot, and displays the spot position and fit parameters in real time.

Setup

pip install -r requirements.txt

The Thorlabs TSI SDK (thorlabs_tsi_sdk) is not on PyPI and must be installed separately from the Thorlabs Scientific Imaging SDK.

On pos-control these requirements are usually already preinstalled, and the corresponding environment can be actived via conda:

conda activate positioner-env

Usage

Run from the repository root:

python -m ui.liveview --exposure 10000

Key arguments:

Argument	Default	Description
--exposure	(required)	Camera exposure time in µs
--plate-scale	85.9	Plate scale in µm/px
--bin	4	Spatial binning factor for Gaussian fit
--interval	0.5	Minimum seconds between frames
--camera	0	Camera index

Saving data

Press w at any time to write all accumulated data to disk. Two files are created with the same name stem: a CSV containing one row per frame, and a PDF snapshot of the current figure. The output path can be set with --output; otherwise files are named tilt_YYYYMMDD_HHMMSS.csv/.pdf in the working directory.

The CSV columns are time_s, segment, x_mm, y_mm, sigma_x_mm, sigma_y_mm, amplitude_counts. The segment column records which data segment each measurement belongs to — segments are incremented by pressing Space and reset to 0 by pressing c. Pause/resume break-points are stored as NaN rows.

Keyboard shortcuts

Key	Action
c	Clear all accumulated data and reset the clock
p	Pause / resume acquisition
i	Toggle camera image between linear and log scale
Space	Start a new data segment.

Camera Live Viewer

The script ui/cameraview.py implements a simple live camera viewer of the Thorlabs CS126MU camera. No spot finding is carried out, and no pixel to mm conversion is done!

Setup

Equivalent for the ui.liveview.py utility above!

Usage

Run from the repository root:

python -m ui.cameraview --exposure 10000

Key arguments:

Argument	Default	Description
--exposure	(required)	Camera exposure time in µs
--stack	1	Average multiple consecutive frames
--camera	0	Camera index
--display-bin	1	Spatial binning for faster image display