Patent ID: 7324414

Claim:
In a recording apparatus for recording a signal on a disk by irradiating a laser beam on said disk, a recording apparatus comprising: a photoreceptor for receiving a reflected laser beam obtained when said laser beam is irradiated on said disk; a gate circuit to which a signal outputted from said photoreceptor is supplied; a providing circuit having an integrating circuit and a hold circuit, and being operable to receive an output signal from the gate circuit and to provide a predetermined reference value therefrom; and a level comparing circuit for comparing a value of the output signal from said gate circuit with the predetermined reference value, wherein upon recording, said gate circuit is controlled in synchronism with said signal to be recorded in such a manner that it outputs a signal of a predetermined period from output signals supplied from said photoreceptor to said gate circuit as said output signal and an output signal of said level comparing circuit is outputted as detected results of vibrations of said disk or vibrations of a light source for outputting said laser beam.