Daylight

2023

Overview

An experimental AR headset project exploring transparent waveguide optics for extended screen real estate. The system features custom-designed PCBs including a main logic board with STM32 microcontroller, display driver IC, and 9-axis IMU for head tracking, along with a power supply unit, connector board, and touchpad interface. While the electronics and mechanical design progressed well, the waveguide optics proved too complex to develop independently, highlighting the challenges of optical system design.

Technology

Embedded Systems PCB Design Micro OLED Displays KiCad STM32 Display Driver IC IMU Capacitive Touch Optics Design Waveguide Development Blender Onshape

Schematics

The device receives DisplayPort input through a USB-C port on the headband behind the left ear. A diverging cable splits the connection to both a power supply unit, which supplies the various voltages required by the main logic board and displays, and the data connection to the main logic board. The main logic board features a display driver IC (LT7911D), an STM32-based microcontroller, and a 9-axis IMU that detects and adjusts the output image according to the user's head movements. A touchpad board with a touch IC is located on the right temple of the device for user input.

Main Logic Board

Connector Board

Power Supply Unit

Touchpad Board

PCB Layouts

The main logic board

The power supply unit

The USB-C connector board

Process

This was the development board for driving these displays.

To rapidly iterate on waveguide prototypes, I built a testing setup that allowed me to quickly swap between different waveguide designs. This modular approach enabled efficient evaluation of optical performance and helped identify the most promising designs for further development.

The optics design proved to be more complex than I initially anticipated, requiring resources and expertise beyond what I could provide independently. I reached out to potential collaborators at the university and explored partnerships with private companies specializing in optical systems, but unfortunately, these efforts didn't materialize into a viable path forward for the project.

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