Jack Yu

Freshman at Caltech majoring in Physics

September 2025 - Raspberry Pi Near-Infrared Imaging

Unsatisfied with the awkward usage of IR viewers, I developed a camera system using the Raspberry Pi Camera Module 3 Noir, which is built around the Sony IMX708 sensor. Unlike the standard Pi Camera, the Noir version lacks an infrared filter, enabling us to capture near-infrared light. This makes it especially useful for visualizing and aligning laser systems in the near-IR range, many of which would otherwise be invisible to the naked eye. Combined with autofocus and a compact integration, the setup provides a lightweight, portable, and eye-strain-free alternative to traditional infrared viewers.

To operate the system, I built a full-featured graphical user interface (GUI) in Python using PyQt5 and picamera2. The GUI simplifies tasks like live preview, image capture, and video recording, while also offering custom cropping, magnification, and various focus modes.

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Pi Camera Noir setup view 1
Camera can be setup in many impossible angles
Infrared imaging example
3D printed articulating mount
Pi Camera Noir setup view 2
Display saves space
Captured near-IR laser alignment
Portable setup (at probe station)
Compact Pi Noir camera integration
Selfie taken with camera (12MP)

Snapshots from Summer 2025

I worked on a mechanical fixture to AR coat a Lithium Niobate waveguide, and built a U-bench external cavity setup. At the same time, I set up a Raspberry Pi near-infrared camera system with autofocus, which is more convenient than using a traditional infrared viewer.

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AR coating fixture SolidWorks model
AR coating fixture (SolidWorks)
Tangible AR coating fixture
Tangible AR coating fixture
U-bench SolidWorks model, view 1
U-bench model (SolidWorks, view 1)

Senior Project - Fall 2025

My senior project was to set up an External Cavity Diode Laser (ECDL), to ultimately characterize AR coatings on gain chips. Along the way, I machined many custom optomechanical components, including flexure attachments, and a custom mount for AR coating in a Veeco Spector.

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Senior Project Summary Slide
Senior Project Summary Slide (Summer 2025)
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Etalon Characterization & Summary 2024 Research Summary

Conducted Fabry-Pérot etalon measurements and compiled a general summary of my 2024 research into this slideshow, which I presented to my department.

My data and experimental setup was presented to DARPA.