摘要:
In an optical system for an oblique incidence interferometer, first and second prisms are used for luminous flux dividing and for luminous flux combining, respectively. Reference light and measurement light are separated from each other at a surface where collimated coherent light enters or exits from the first prism, whereas the reference light and measurement light are combined together at a surface where the measurement light enters or exits from the second prism.
摘要:
In an interferometer optical system comprising a reference standard having an entrance surface on which a luminous flux from a light source is incident and a reference plane on which the luminous flux entering from the entrance surface is obliquely incident, an angle within the range of 10° to 30° is formed between the entrance surface and reference plane of the reference standard.
摘要:
A process of measuring a shape while changing the relative posture of an microscopic interferometer to a sample lens which is rotated about a rotation axis is divided into a process of measuring a top surface in a state where the sample lens is supported from a back surface and a process of measuring a back surface in a state where the sample lens is supported from the top surface. By combining first shape information of a flange side surface acquired by the process of measuring the top surface and second shape information of the flange side surface acquired by the process of measuring the back surface, the relative positional relation between the sample top surface and the sample back surface is calculated.
摘要:
A reference lens for an interferometer is constructed so that light transmitted by a partially reflecting reference spherical surface may be converged, toward a focal point that coincides with the center of curvature of the reference spherical surface, and reflected from a subject spherical surface that also has its center of curvature at the focal point. Measurement of the shape of the subject spherical surface is possible based on the interference of two light beams, one reflected by the subject spherical surface and one reflected by the reference spherical surface. The reference lens, which may include five or six lens components or lens elements, includes a negative meniscus lens component, a positive lens group, and a positive lens component. Specified conditions are satisfied to provide a reference lens that has favorable correction of aberrations, is compact, and can measure the surface accuracy of a wide range of convex spherical surfaces.
摘要:
The relative position of a test surface is sequentially changed from a reference position where a surface central axis is aligned with a measurement optical axis such that the measurement optical axis is sequentially moved to a plurality of annular regions obtained by dividing the test surface in a diametric direction. The test surface is rotated on a rotation axis whenever the relative position is changed. Measurement light composed of a plane wave is radiated to the rotating test surface, and a one-dimensional image sensor captures interference fringes at each of a plurality of rotational positions. The shape information of each annular region is calculated on the basis of the captured interference fringes at each rotational position, and the shape information is connected to calculate the shape information of the entire measurement region.
摘要:
Respective regional form information items obtained from regional interference fringe images corresponding to partial regions of a spherical surface to be inspected are transformed into regional synthesis form information items corresponding to a common coordinate system set for aperture synthesis by using a relationship among a polar coordinate system of the spherical surface, a plane coordinate system of an imaging plane, and the common coordinate system. Thus obtained regional synthesis form information items are subjected to aperture synthesis processing, so as to determine the overall form information of the spherical surface.
摘要:
An imaging optical system for an oblique incidence interferometer comprises first and second optical systems and an intermediate imaging surface therebetween. Each of the first and second imaging optical systems comprises two telecentric lenses, arranged afocal to each other, having respective focal lengths different from each other. A first image of a surface to be inspected having a deformed aspect ratio with respect to this surface is formed on the intermediate imaging surface by way of the first imaging optical system. The second imaging optical system is arranged such that the first image is focused onto the imaging surface of the interferometer as a second image corrected so as to have substantially the same aspect ratio as that of the surface to be inspected.
摘要:
An imaging lens having three lens groups is designed so that image aberrations of an object at infinity (i.e, a collimated beam) and of an object at a finite distance are very well-corrected so that the imaging lens is particularly suitable for use imaging interference patterns formed on a screen by a grazing incidence interferometer. The imaging lens is composed of the following lens components, in successive order from the most object side: a first lens component having an overall meniscus shape with its concave surface on the object side, a second lens component having negative or positive refractive power, and a third lens component of positive or negative refractive power. The refractive power of the second lens component and the third lens component are always of opposite sign, and specified conditions are satisfied in order to assure high quality imaging. Each lens component may be formed of a single lens element or of multiple lens elements.
摘要:
A long flexible waveguide is fabricated by corrugating a thin-walled tube circular in section and then molding the corrugated tube so as to make the shape of its section substantially rectangular. The long flexible waveguide has a substantially rectangular section wherein a corrugating pitch P falls within a range of .lambda..sub.g /10
摘要:
The relative position of a test surface is sequentially changed from a reference position where a surface central axis is aligned with a measurement optical axis such that the measurement optical axis is sequentially moved to a plurality of annular regions obtained by dividing the test surface in a diametric direction. The test surface is rotated on a rotation axis whenever the relative position is changed. Measurement light that travels while being converged by a Mirau objective interference optical system is radiated to the rotating test surface, and a one-dimensional image sensor captures interference fringes at each of a plurality of rotational positions. The shape information of each annular region is calculated on the basis of the captured interference fringes at each rotational position, and the shape information is connected to calculate the shape information of the entire measurement region.