Patent ID: 7038980

Claim:
A recording apparatus for recording a signal on a disk by irradiating a laser beam on said disk, the recording apparatus comprising: an optical head having a photodiode 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 optical head is supplied; a level comparing circuit for comparing a value of an output signal from said gate circuit with a reference value, wherein upon recording, said gate circuit is controlled in synchronism with said signal to be recorded in such a manner that it may output a signal of a first predetermined period from output signals to be supplied from said optical head 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; an integrating circuit for integrating a value of the output signal of said gate circuit over a second predetermined period when the recording is started; and a hold circuit for holding an integrated result of said integrating circuit and wherein a hold output of said hold circuit is supplied to said level comparing circuit as said reference value.