PURPOSE: To enable setting a projection system whatever the projection system is, by interpolating the image stored in a ROM and making adjustment by the result thereof.

CONSTITUTION: A CPU 31 controls respective parts according to the program stored in a ROM 32 and executes an adjustment operation. Stepping motors 10r, 11r, 10g', 11g', 10b, 11b are driven via an input/output port 37, an amplifier circuit 40 and a switcher 39a. The zero reference positions thereof are detected by photocouplers 50r, 52b and are taken into the input/output port 37 via a switch 39b. IR rays can be emitted and a prescribed command can be inputted to a remote controlled photodetecting section 36 by operating a commander 35. This command is supplied via the input/output port 37 to the CPU 31. Further, the projection system data on site is computed by an interpolation method using the data in a PM 32 and the automatic adjustment to the computed value is made.