The CRT requirement has pleasantly eroded recently.
A kickstarter a few years back for the Sinden light gun [1] realized that by using webcams, some quick image processing and perspective transforms, you could make a light gun work anywhere and could get real-time performance on non-CRTs by essentially adding a small border region of the screen, making it work on essentially any monitor. He filmed and wrote extensive technical breakdowns about the build process and mechanics at play, which were great.
The maker also seems to have had a solid understanding of what made those old light gun games cool, because he made sure to build versions with solenoid-based recoil as well as the big chunky metal foot pedal you’d use for games like time crisis.
Sinden is no longer the way to go. Most lightgun enthusiasts have now gone the Gun4IR route [0]. It uses the IR sensor from a WiiMote plus a microcontroller in the gun (either a gutted commercial controller like the PS Guncon, a modified Nerf or similar, or something straight up 3d printed) and four IR LEDs placed around a monitor / TV at the midpoints of each each. This system is extremely accurate and there is no flashing border around the screen like with Sinden. Unfortunately, the whole shooting match (see what I did there?) is closed source code and (as of now) Window's only for the calibration-based PC software.
The current open source competitor to Gun4IR is the Samco light gun [1]. It uses four LEDs as well, but with two on the top edge and two on the bottom edge of the screen. A couple Wii LED bars will do the job here as well. I don't think it is quite as accurate as the Gun4IR as I don't think it accounts for perspective correction if you move from the position it was originally calibrated at. But...
Sam & a few others are readying a new design called OpenFire [2] that will be at least on par accuracy-wise as Gun4IR and will be fully open source and cross platform. It should be available relatively soon. Pair this with the PiCon [3] and you have a lightgun with a pretty crazy feature set. All the guns mentioned support some kind of solenoid & rumble support, but the PiCon kicks it up a notch with exclusive OpenFire features like an OLED display, NeoPixel LED, accelerometer, and analog joystick.
That's true, but crts are basically free and plug and play while looking extra crispy. I think if you're okay spending a lot more to get an equivalent setup those are good options, but harder to recommend.
A kickstarter a few years back for the Sinden light gun [1] realized that by using webcams, some quick image processing and perspective transforms, you could make a light gun work anywhere and could get real-time performance on non-CRTs by essentially adding a small border region of the screen, making it work on essentially any monitor. He filmed and wrote extensive technical breakdowns about the build process and mechanics at play, which were great.
The maker also seems to have had a solid understanding of what made those old light gun games cool, because he made sure to build versions with solenoid-based recoil as well as the big chunky metal foot pedal you’d use for games like time crisis.
[1] https://youtu.be/grcGpr_8W9Y?si=z800V7f62dDS1KGs