Patent attributes
Conventional mirror angle control systems require a detection mirror separate from a deflection mirror. Depending on the accuracy with which these mirrors are fitted relative to each other, in products incorporating such control systems, degraded control accuracy may result. Moreover, a separate light source is needed for shining laser light on the detection mirror. This makes it difficult to miniaturize products incorporating these control systems, and leads to increased electric power consumption. To overcome these disadvantages, in the mirror angle control system of the invention, light from a light source is shone on a mirror, and part of the light reflected therefrom is condensed, with a reflective hologram, on a light receiver. Then, based on an electrical signal commensurate with the inclination angle of the mirror as outputted from the light receiver and a target signal, a drive signal is fed to a driver that drives the mirror to rotate.