Abstract: An inspection system inspecting an original with a pellicle, which system includes a light source for providing a light beam, a first detecting device for receiving light produced as a result of passage of the light beam through the pellicle, a second detecting device for receiving light produced as a result of non-passage of the light beam through the pellicle, and a processing system for determining information related to transmissivity of the pellicle, on the basis of outputs of the first and second detecting devices.

Abstract: A displacement detecting system includes a scale provided on a surface of a movable object and having a diffraction grating formed along a predetermined direction, a head unit disposed above the surface of the movable object and having a plurality of detection heads, for detecting displacement of the scale in the predetermined direction, the detection heads being disposed along a direction different from the predetermined direction, and a selecting device for selecting at least one detection head out of the detection heads, for detection of a displacement of the scale in the predetermined direction.

Abstract: An inspecting system includes a light source, an irradiating optical system for irradiating a surface of an object such as a reticle or photomask with light from the light source, a detection optical system for detecting scattered light from the surface of the object, and a light blocking device provided substantially parallel to the surface of the object, the light blocking device having a first light transmitting portion for passing light coming from the light source toward the surface of the object and a second light transmitting portion for passing light coming from an irradiated position on the surface of the object toward the detection optical system.

Abstract: A finder optical system of the present invention includes from the object side an objective lens system of a positive refractive power and an eyepiece system of a positive refractive power. The objective lens system includes from the object side a first lens unit of a negative refractive power, a second lens unit of a positive refractive power and a third lens unit of a positive refractive power. Zooming is performed by moving the first and second lens units. Each of the first and second lens units includes a single lens having at least one aspherical surface. The third lens unit includes a lens prism at least an incident surface of which is an aspherical surface.

Abstract: Disclosed is an inspection method and apparatus: wherein (i) first light having a first state of polarization and a first wavelength, and (ii) second light having a second state of polarization, different from the first state of polarization, and a second wavelength, different from the first wavelength are produced; at least the first light is projected to a position of inspection; and heterodyne interference light produced on the basis of the second light and light scattered at the inspection position and having its state of polarization changed, by the scattering, from the first state of polarization, is detected.

Abstract: When inspecting the presence of foreign matter on a surface to be inspected by scanning the surface with a light beam from a light source utilizing a scanning system, and receiving scattered light from the surface by a detector, a correlation is utilized between a signal representing first scattered light obtained from the detector when the light beam scans a first line on the surface, and a signal representing second scattered light obtained from the detector when the light beam scans a second line displaced from the first line by a predetermined amount in a direction orthogonal to the direction of the first line.