It'd be a pain, but possible. See threads about VGA out if you want to use the analog circuitry to drive the screen, but keep in mind it needs 15kHz horizontal refresh rate, not 31kHz like a normal monitor. If you intend to drive it using the built-in LCD controller, I can get you the model number and link you to the datasheet for the LCD inside the PSOne screen. The native res of the LCD is the same, so it shouldn't be too hard to hack the LCD cable and kernel to run a PSOne LCD.