Student: Imane Raihane
Project Title: An Affordable Development Kit for Lensless Imaging
Semester: Spring 2025
Program: B.Sc. in Computer Science, EPFL
1. Calibration Box Development : Measuring PSF
To accurately measure the PSF : a point light source is required and must be precisely aligned relative to the sensor. This motivates the need for a stable, reproducible, and adjustable calibration setup.
| Component |
Quantity |
Price (CHF) |
Webshop / Link |
| 2060 V-Slot Aluminium Extrusion |
1 |
17 |
Shop |
| Stepper Motor 28BYJ-48 + Drivers |
1 |
— |
|
| M5 Screws |
10 |
1 |
SPOT EPFL |
| M3 Screws |
10 |
1 |
SPOT EPFL |
| 2GT Timing Belts (6 mm width) |
2 |
— |
SPOT EPFL |
| 30-Tooth 2GT Pulley |
1 |
— |
SPOT EPFL |
| Linear Rods (8 mm) |
2 |
1.4 |
SPOT EPFL |
| Linear Bearings (8 mm) |
4 |
4 |
SPOT EPFL |
| Small Idler Pulley (5 mm bore) |
2 |
— |
SPOT EPFL |
| Big Idler Pulley (5 mm bore, 6 mm width) |
1 |
— |
SPOT EPFL |
| Solid V-Wheels |
4 |
12 |
Shop |
| Printed Material (custom parts) |
– |
– |
STL Files |
Here is the inspiration for Alignment Control Code : Link
2. Improving the Capture Process : Automatic Determination of Parameters
Auto Exposure
- Automatically select exposure time to avoid under/overexposure
How It Works
In all cases, an initial manual exposure time must be provided : it serves as a starting point for the fine-tuning process. The system will then iteratively adjust until optimal exposure is reached :
For more details about the implementation, here is the PR related to it : #174
To enable automatic exposure adjustment, set the following flags in your command:
auto_exp_psf = true → when capturing a PSFauto_exp_img = true → when capturing a Regular image
PS : By default, both flags are set to false
RGB Gain Correction
To perform color correction, we compute the red and blue gains that align the three RGB channel curves into a single unified curve :
For more details about the implementation, here is the PR related to it : #175
PS : This method is only valid during PSF capture, as it requires a known white object.
3. Lensless Imaging WebApp
- Repository : Link
- Features:
- Web interface controls full imaging pipeline
- Headless operation: only requires browser on same network
- Step-by-step GUI and online documentation included
Student: Imane Raihane
Project Title: An Affordable Development Kit for Lensless Imaging
Semester: Spring 2025
Program: B.Sc. in Computer Science, EPFL
1. Calibration Box Development : Measuring PSF
To accurately measure the PSF : a point light source is required and must be precisely aligned relative to the sensor. This motivates the need for a stable, reproducible, and adjustable calibration setup.
Static Calibration Box :
Basic and functional : interchangeable aperture sizes and adjustable LED brightness.
STL files : STL Files Box.zip
X/Y Moving Calibration Box :
Here is the inspiration for Alignment Control Code : Link
2. Improving the Capture Process : Automatic Determination of Parameters
Auto Exposure
How It Works
In all cases, an initial manual exposure time must be provided : it serves as a starting point for the fine-tuning process. The system will then iteratively adjust until optimal exposure is reached :
For more details about the implementation, here is the PR related to it : #174
To enable automatic exposure adjustment, set the following flags in your command:
auto_exp_psf = true→ when capturing a PSFauto_exp_img = true→ when capturing a Regular imagePS : By default, both flags are set to
falseRGB Gain Correction
To perform color correction, we compute the red and blue gains that align the three RGB channel curves into a single unified curve :
For more details about the implementation, here is the PR related to it : #175
PS : This method is only valid during PSF capture, as it requires a known white object.
3. Lensless Imaging WebApp