Abstract: A diffraction grating lens according to the present invention includes a lens body 171, and a diffraction grating which has been formed on the surface of the lens body 171 and which includes diffraction steps and concentric annular zones. Each annular zone is interposed between two adjacent ones of the diffraction steps. The lens body 171 is made of a first material that has a refractive index n1 (?) at an operating wavelength ?. The diffraction grating is in contact with the air. At least one of the annular zones has one of a recess 11 and a protrusion 12 provided for at least a part of the inner end portion thereof and the other provided for at least a part of the outer end portion thereof, respectively. The diffraction grating lens satisfies the relation 0.9 ? d ? m · ? n 1 ? ( ? ) - 1 ? 1.1 ? d where d represents a designed step length of the diffraction step 14 and m represents an order of diffraction.

Abstract: A diffraction grating lens according to the present invention is a diffraction grating lens 11 including: a lens body 12; and a plurality of diffraction steps relative to a base shape and a plurality of diffraction gratings 13 interposed between the diffraction steps, provided on a surface of the lens body 12. The lens body 12 is made of a first material having a refractive index n1(?) at a used wavelength ?; the diffraction grating 13 is in contact with air; and the relationship of an inequality below is satisfied, where d is a design step length of the diffraction steps, and m is an order of diffraction.

Abstract: A measurement method and an evaluating apparatus are provided which accurately evaluate the light amount of a spot beam, the diffraction efficiency, and the intensity distribution in the optical axis direction by detecting even a weak diffracted beam in an arbitrary wavelength range converged by a diffraction optical element as an imaging lens. Light emitted from a white light source passes through a wavelength band-pass filter and is diaphragmed by a pinhole slit. The resultant light is paralleled by a collimator lens and enters a diffraction optical element as an imaging lens. The light getting out from the diffraction optical element is converged to be a spot beam, is magnified by a microscope 18, and is then projected on a CCD. A distance changing member changes the distance between the CCD and the diffraction optical element, and then, the intensity distribution in the optical axis direction is measured.

Abstract: A diffraction grating lens of the present invention includes a lens base 51 having a surface 51b obtained by providing a diffraction grating 52 on a base shape. The diffraction grating 52 includes a plurality of zones 61A and 61B and a plurality of first diffraction steps 65A and second diffraction steps 65B located between the plurality of zones; the lens base is made of a first material whose refractive index is n1(?) at a working wavelength ?; and the first diffraction steps 65A and the second diffraction steps 65B have substantially the same height d. The height d satisfies Expression (1) below, where m denotes a diffraction order. A first surface 66A on which tips 63A of the first diffraction steps 65A are located and a second surface 66B on which tips 63B of the second diffraction steps 65B are located are at different positions from each other on an optical axis 53.

Abstract: A diffractive lens according to the present invention has the function of focusing light. The diffractive lens has a side on which a diffraction grating is arranged on either an aspheric surface or a spherical surface in its effective area. The diffraction grating has n0 phase steps, which are arranged concentrically around the optical axis of the diffractive lens. And the radius rn of the circle formed by an nth one (where n is an integer that falls within the range of 0 through n0) of the phase steps as counted from the optical axis of the diffractive lens satisfies rn=?{square root over (a{(n+c+dn)?b(n+c+dn)m})}{square root over (a{(n+c+dn)?b(n+c+dn)m})} where a, b, c and m are constants that satisfy a>0, 0?c<1, m>1, and 0.05 ? b 0 < b < b 0 b 0 = 1 mn 0 m - 1 and dn is an arbitrary value that satisfies ?0.25<dn<0.25.

Abstract: A diffractive optical element (10) includes a substrate (11), a protective film (13a, 13b), and a diffraction grating (12a, 12b) disposed between the substrate (11) and the protective film (13a, 13b), wherein the diffraction grating (12a, 12b) is formed of a composite material containing a resin and inorganic particles, a volume ratio of the inorganic particles with respect to the composite material is equal to or smaller than 50% by volume, and the diffraction grating (12a, 12b) has a thickness of equal to or smaller than 20 ?m. Since the diffractive optical element (10) uses the composite material containing the resin and the inorganic particles as a material for the diffraction grating (12a, 12b), which is relatively difficult to process, the moldability improves compared with the conventional case of using glass, etc.

Abstract: A diffractive optical element according to the present invention includes: a lens body 11 with a blazed grating 13 on an aspheric surface 11a thereof; and an optical adjustment layer 15 that covers the diffraction grating 13. The lens body 11 is made of a first material 14a and the optical adjustment layer 15 is made of a second material 14b that has a higher refractive index than the first material 14a. The diffraction grating 13 has a number of ring zones that are arranged concentrically around an optical axis, where the height of each ring zone with respect to the aspheric surface 11a of the lens body 11 is represented by an increasing function of a distance r from the optical axis. The increasing function is represented by a phase polynomial that uses the distance r as a variable and that has a magnitude of 3/4? to 7/4? when r=0.

Abstract: An imaging optical system according to the present invention includes a lens that has first and second surfaces and that has a diffraction grating on only one of the first and second surfaces. If the diameter of an effective area, which is defined by a light ray that has entered the lens with a maximum angle of view, is D when measured on the surface with the diffraction grating, an F number of the imaging optical system at the maximum angle of view is Fno, a d-line Abbe number of the lens is ?d, and an F number of an axial bundle of rays is F, then the average diffracting ring zone pitch of the effective area satisfies 0.008 ? ? D × Fno ? 0.

Abstract: A measurement method and an evaluating apparatus are provided which are capable of easily and accurately evaluating the light amount of a spot beam, the diffraction efficiency, and the intensity distribution in the optical axis direction by detecting even a weak diffracted beam in an arbitrary wavelength range converged by a diffraction optical element as an imaging lens.

Abstract: A diffractive imaging lens 10 includes a surface on which a diffraction grating pattern is formed. The diffraction grating pattern is formed of a plurality of steps formed concentrically with an optical axis (25) at a center. The diffraction grating pattern is formed such that a first portion where amounts (di) of the steps are substantially the same in a radial direction of concentric circles and a second portion, outside of the first portion, where amounts (di) of the steps decrease with distance from the optical axis 25 are provided, or such that the amounts (di) of the steps decrease with distance from the optical axis 25 over the entire diffraction grating pattern.

Abstract: The present invention reduces the angle dependence of diffraction efficiency by taking the diffraction pitch and diffraction step of an optical element with a diffraction grating such as a lens into account. Specifically, for that purpose, an optical element that has a first group of diffraction grating portions 20 around an optical axis 10 is covered with a protective coating 14, and a second group of diffraction grating portions 21 are arranged on the surface of the protective coating 14 far away from the optical axis 10.

Abstract: A measurement method and an evaluating apparatus are provided which are capable of easily and accurately evaluating the light amount of a spot beam, the diffraction efficiency, and the intensity distribution in the optical axis direction by detecting even a weak diffracted beam in an arbitrary wavelength range converged by a diffraction optical element as an imaging lens.

Abstract: In a refraction lens having an aspheric shape formed thereon and having a positive power, a diffraction grating is formed on at least one of the faces of the refraction lens. In order to reduce the curvature of field and the chromatic aberration in a well-balanced manner, the zonal pitch of the diffraction grating is constituted so as to satisfy the following conditional expression. [ eq . ? 19 ] 0.21 ? ? m 2 ? v d ? ? ? f h max < ? min < 0.30 ? ? m 2 ? v d ? ? ? f h max ( 1 ) Herein, ?min is a minimum zonal pitch 12; m is an order of diffraction; ?d is an Abbe number of the lens substrate material with respect to the d-line; ? is a wavelength; f is an effective focal length; and hmax is an effective radius 13 of the face on which the diffraction grating is formed.

Abstract: An optical element according to the present invention is an optical element including: a first light transmitting layer having a first sawtooth blazed surface 10, the first light transmitting layer including a plurality of first light-transmitting slopes 12 defining a first blaze angle ?; and a second light transmitting layer having a second sawtooth blazed surface 20 including a plurality of second light-transmitting slopes 22 defining a second blaze angle ?, the second light transmitting layer being in contact with the first sawtooth blazed surface 10 of the first light transmitting layer. A tilting direction of the first light-transmitting slope 12 and a tilting direction of the second light-transmitting slope 22 are opposite.

Abstract: A diffractive lens 11 according to the present invention includes: a lens base 18, which has a second surface 13 with first and second groups of diffraction grating portions 20 and 21; and a protective coating 17, which is arranged on the first group of diffraction grating portions 20. The first group of diffraction grating portions 20 has a first group of diffraction steps and the second group of diffraction grating portions 21 has a second group of diffraction steps, which is lower in height than the first group of diffraction steps. One of the respective materials of the base 18 and the protective coating 17 has a higher refractive index and a greater Abbe number than the other material. And the second group of diffraction steps is not covered with the protective coating 17.

Abstract: According to the present invention, a small-sized double-lens imaging optical system whose chromatic aberration is corrected even at a super wide angle of 150° or more can be provided. The double-lens imaging optical system of the present invention includes a concave lens, and a convex lens having a diffraction grating provided thereon, and satisfies the following conditional expression (1): 4.5<P1=(1?f/fa)·?d<9.0??(1). Herein, f is an effective focal length of the double-lens imaging optical system; fa is an effective focal length of the double-lens imaging optical system excluding the diffraction grating; and ?d is an Abbe number of the material of the convex lens with respect to the d-line. As a result, chromatic aberration can be well corrected even with respect to rays entering at high angles of view.

Abstract: A three-dimensional optical waveguide is formed by laminating planar substrates such as a plurality of lens substrates and, an isolator substrate and a wavelength division multiplexing filter, the optical substrates at least include a waveguide substrate having a waveguide and a reflecting surface. In the three-dimensional optical waveguide, the planar substrates are positioned by markers integrally formed on at least two of the planar substrates. Light directed into the waveguide is reflected by a reflecting surface and passes through the lens substrates and the isolator substrate.

Abstract: A diffractive optical element that can be molded readily, an imaging apparatus incorporating the diffractive optical element, and a method for manufacturing the diffractive optical element are provided. A diffractive optical element (10) includes a substrate (11) that is made of a first material containing a resin and has a surface (11a, 11b) on which a diffraction grating pattern (12a, 12b) is formed, and a coating film (13a, 13b) that is made of a second material containing a resin and is disposed so as to be in contact with a portion of the diffraction grating pattern (12a, 12b), and at least one material selected from the first material and the second material is a composite material containing inorganic particles.

Abstract: A composite material (10) includes a resin (12), and first inorganic particles (11) dispersed in the resin and containing at least zirconium oxide. The composite material has a refractive index at the d line nCOMd of not less than 1.60 and an Abbe's number ?COM of not less than 20, and satisfies a relationship nCOMd?1.8?0.005 ?COM. This composite material exhibits both a high refractive index and low dispersion in good balance, and has excellent workability. Accordingly, using this composite material makes it possible to realize a small optical component having favorable wavelength characteristics.

Abstract: An image processing device that can highly precisely correct an image with a degraded image quality due to the unnecessary diffracted light generated in the optical system including the diffractive optical element is provided.