Recent submissions

Comment · 1 month ago
Wow, they have a laser with a shutter! The Litiholo kit just gives you a basic laser diode, and they don't tell you that you have to let the laser warm up before exposing the hologram. I made so many smeared/blurry holograms before I figured out you have to block the laser, turn it on and warm up, then unblock the laser.
Comment · 1 month ago
You can get holographic film and kits from http://www.litiholo.com. These are not silver halide but are Covestro Bayfol HX photopolymer film which require no post processing.
Comment · 4 months ago
Fusion 360 complains about Windows 10, but it still runs fine.
Comment · 6 months ago
Comment · 1 year ago
This is incredible! Thanks for posting.
Comment · 1 year ago
For me, the camera is just looking up and spinning clockwise. I tried in both Brave and Chrome.
Comment · 2 years ago
Unfortunately, DisplayPort and HDMI specifications are kept private unless you're a paying member. I've successfully implemented DisplayPort 1.2 in an FPGA from specification documents I found, but I could never find the specification for anything better.
Comment · 2 years ago
Comment · 2 years ago
Comment · 2 years ago
Comment · 2 years ago
The big push is currently towards microLED displays because of the high brightness and fast modulation speed. Yield is not yet good, and there's difficulty in growing all colors on the same substrate. Picking and placing different color LEDs onto the same panel is not cost effective. Red microLEDs are also not yet as bright as blue and green.

There was a push towards micro liquid crystal panels with laser illumination to create holographic images with depth. There are several startups still pursuing that, but the image quality isn't very good at the moment.

The latest advancement has been in the optics with moving to pancake lenses to reduce the length of the optical path from the display to the eye. The Meta Quest 3 has a smaller form factor than previous generations because of this.

Comment · 2 years ago
I work on VR/AR headsets where there's a drive for higher refresh rate displays to do things like multiple focal planes with the extra frames.
Comment · 2 years ago
Standard displays are 60 Hz. You need a much higher framerate because not only do you want 60 frames a second, but you also want some number of frames per angular rotation. For 1° of angular resolution, you would need: 360°*60 Hz = 21,600 Hz display. Liquid crystals can be modulated at KHz speeds, but you're not going to find associated driving circuitry to do that. It's not easy, and there's no demand for it.

A TI DLP DMD can modulate at those high speeds, and there's readily available driving circuitry for it. However, it's a small reflective based display designed for projectors, and you would then need a light source to reflect off of it.

MicroLEDs would let you increase your pixel pitch with fast modulation frequency, but the display area is still small at the moment because of low yields. You also need a custom chip to drive the microleds at the required high framerate.

Comment · 3 years ago
Ended on a hand of: K J A A Q and did not receive the Jacks or Better $1 payout. According to a brief search about the rules of video poker, a pair of aces is considered better than a pair of jacks.
Comment · 3 years ago
"Uh oh!" So, what happened next?

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