Laser-Excited Phosphor Scanning Display

Retrace

This isn't a CRT simulation.
It's the same phosphor process — just
driven by a laser instead of an electron gun.

Physically real. Solid-state. No lead, no high voltage.

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01 — The Idea

Three ways to make
a picture

Every screen you've ever used does one of two things. Here's what Retrace does instead.

Every modern screen

Millions of tiny lights

Your phone, your TV, your monitor — they're all grids of millions of individual LEDs or backlit pixels, each one switching between red, green, and blue. The whole grid is on at once, all the time. Every single pixel is its own little light source.

Old CRT televisions

One beam, one line at a time

An electron gun shoots a beam at a phosphor-coated screen, painting the picture one line at a time, left to right, top to bottom — so fast your eye sees a full image. The glow, the bloom, the faint lines between rows? That's just what happens when phosphor lights up and fades.

Retrace

Same idea, new parts

Replace the electron gun with a laser and a tiny mirror. Same painting motion, same phosphor glow, same natural fade. You get the image quality people loved about CRTs — but in a flat panel, with no lead glass, no giant tube, and no 25,000 volts.

That's the whole concept. The rest of this page goes deeper into the engineering, but this is the core of it — same light-painting process, modern components.

02 — Concept

The CRT was never about
the electron gun

The electron gun was just the excitation source they had in the 1950s. The part that actually made the picture was always the phosphor — a material that glows when you hit it with energy and then fades on a natural decay curve. That's the whole trick.

Retrace swaps the electron gun for a scanning laser and the glass phosphor screen for a flat electroluminescent panel. You get the same image formation — real scanlines, real persistence, real bloom — without the tube, the weight, the 25kV flyback, or the lead glass.

CRTs didn't lose to LCDs on image quality. By most measures they were better. They lost on form factor — the electron gun architecture needed depth, and the industry hit a wall on size and weight that it couldn't engineer around.

The industry accepted that tradeoff and has been clawing back ever since — HDR, high refresh, local dimming, increasingly elaborate CRT shaders. Retrace doesn't try to simulate any of that. It just goes back to the phosphor.

Component Mapping

Electron gun RGB laser diodes
Deflection yoke MEMS / galvo mirrors
Phosphor coating EL phosphor panel
Phosphor decay EL decay characteristics
Analog dials Software-defined params
EL PHOSPHOR PANEL
03 — System

Three off-the-shelf parts

Scanning

MEMS Mirror Array

A laser beam rasters across the screen — left to right, top to bottom — the same sweep pattern as a CRT electron beam. The mirrors oscillate on two axes at thousands of Hz. These are mass-produced parts; LiDAR and picoprojector companies already sell dev boards.

Light Source

RGB Laser Diodes

As the beam sweeps, each colour channel modulates intensity at pixel-level timing — painting brightness and colour point by point, same as a CRT modulates beam current. These are the same diodes in Blu-ray drives, laser cutters, and pocket projectors. Nothing exotic.

Screen

EL Phosphor Panel

Zinc-sulfide phosphor compounds glow under laser excitation and then fade naturally. That decay is the whole point — it gives you physically real scanline structure, real persistence curves, actual ambient glow, and genuine bloom. These aren't effects. They're material properties.

Every one of these components was lab or military hardware in 1990. Today they're commodity. The idea was never the hard part — the parts just didn't exist yet at the right price.

04 — Advantages

What you can't get
from a shader

vs. CRT Shaders

No GPU overhead

Shaders have to fake every part of a CRT image — scanline masking, sub-pixel layout, beam bloom, halation, aperture grille, phosphor gamma. That's real compute on top of the actual frame render. Retrace produces all of it as a free side effect of the physics. The phosphor just does that.

vs. Vintage CRTs

Not a ticking clock

Every surviving CRT is older than it was yesterday. They need high voltage, they contain lead, they can't be manufactured or repaired at any kind of scale. Retrace is solid-state — no toxic materials, no flyback transformer, no countdown to a dead tube.

Energy

Light only where the image needs it

An LCD backlight runs at full power all the time — the liquid crystal layer then blocks most of it to form the picture. You're paying to generate light and then paying again to throw it away. Retrace puts laser energy only where brightness is needed. A dark scene with a few bright highlights draws almost nothing. For typical content, average power should be meaningfully below an equivalent LCD.

05 — Roadmap

Research & Development

Phase 01 1–3 months
Research & Validation
Can we actually make this work? Source MEMS mirrors and laser diodes, dig into existing laser projector control literature, and answer the first real question: does EL phosphor respond to laser excitation with enough spatial sharpness at scanning speeds to form a usable image?
Phase 02 3–6 months
Proof of Concept
Single-colour laser on a small EL panel. The only question at this stage is whether the image formation is physically authentic — real scanlines, real persistence. Resolution and brightness are secondary.
Phase 03 6–12 months
RGB & Control System
Full RGB laser array, beam modulation timing, MEMS control firmware, basic frame buffer input.
Phase 04 12–18 months
Screen & Optics
Optimise panel size and phosphor coating, deal with laser speckle, refine beam optics and edge geometry.
Phase 05 18–24 months
Software & Profiles
Driver stack, CRT personality profiles that reproduce specific historical monitors (Trinitron PVM, Commodore 1084, etc.), physical dial controls, and an open format for community-built profiles.
Phase 06 24+ months
Scale & Refinement
Multi-unit sync for larger displays, power profiling, enclosure and industrial design.
06 — Applications

Who this is for

Right now there's nothing between a CRT shader on a flat panel and an actual vintage CRT. That's the gap — a physically authentic display that you can still manufacture and service.

Retro Gaming

Games displayed the way they were designed to look, without shader overhead or the compromises of LCD approximation.

Game Development

A reference display that matches original developer intent for anything designed with CRT output in mind.

Broadcast & Colour

Colourists and studios still reference CRT output as a creative target. This gives them a controllable, repeatable version of it.

Art & Installation

Real scanlines, real glow, real bloom — material properties that shaders can't reproduce, for artists working with light as a physical medium.

Enthusiast & Collector

The vinyl analogy works here. There's proven demand for authentic analogue experiences — Retrace meets it with hardware that isn't dying.

CRT Profiles

Community-shared personality profiles reproducing specific monitors — Sony PVM, Commodore 1084, and whatever else people care about enough to model.

We're building it now

Retrace is in active research. The physics need to be validated before anything else — follow along as we find out if this actually works.

Phase 1 — Research & Validation