Patent ID: 8564767

Claim:
A defect inspecting apparatus which inspects a defect present on an object to be inspected, comprising: a laser light source which generates a laser; a beam spot shaping section including a beam shaping part which has a plane parallel plate for allowing the laser from the laser light source to penetrate therethrough, and a cylindrical lens for shaping the laser having penetrated the plane parallel plate to thereby form a linear beam, and a beam alignment part which reflects the beam having penetrated the beam shaping part and irradiates the beam on the object as a linear beam spot, the beam alignment part being capable of changing an elevation angle of the reflected beam relative to the object; a stage part which supports the object; a detection optical system which detects scattering light reflected from the object supported by the stage part; a control system which controls operations of the beam spot shaping part, the stage part and the detection optical system and detects a defect present on the object, based on the scattering light detected by the detection optical system; wherein the plane parallel plate is arranged inclined by the same angle as an azimuthal angle of the linear beam irradiated on the object, with respect to a plane perpendicular to an optical axis of the laser from the laser light source, and wherein the cylindrical lens arranged in a position thereof symmetric with the plane parallel plate with the plane interposed therebetween.