Patent ID: 7426172

Claim:
An optical module used in an optical pickup so as to emit light onto a recording medium and receive the light reflected from the recording medium to detect an information signal and/or an error signal, the optical module comprising: a body and optical elements disposed in the body, the optical elements comprising: a light source; an optical path changer that changes a path of light emitted from the light source; a main photodetector that receives light that is reflected off the recording medium back to the optical module to detect the information signal and/or the error signal; a hologram element that generates an astigmatism of the light incident onto the optical module; and a beam shaping window disposed at the body that shapes the laser beam emitted from the light source, wherein the beam shaping window is a prism having a first surface disposed perpendicular to the emitted light and a second surface inclined at an angle to an optical axis of the emitted light such that the emitted light is refracted.