Abstract: A laser element includes a photonic crystal layer on which laser light is incident. The photonic crystal layer includes a base layer formed of a first refractive index medium; and a plurality of different refractive index regions formed of a second refractive index medium having a refractive index different from that of the first refractive index medium and disposed in the base layer. The plurality of different refractive index regions includes a first different refractive index region of which a planar shape is an approximate circle, an approximate square, or an approximate polygon having a rotational symmetry of 90° and a first area perpendicular to a thickness direction; and a second different refractive index region having a second area perpendicular to a thickness direction.

Abstract: This semiconductor laser device includes a semiconductor laser chip and a spatial light modulator SLM which is optically connected to the semiconductor laser chip. The semiconductor laser chip LDC includes an active layer 4, a pair of cladding layers 2 and 7 sandwiching the active layer 4, and a diffraction grating layer 6 which is optically connected to the active layer 4. The spatial light modulator SLM includes a transparent common electrode 25, a plurality of transparent pixel electrodes 21, a liquid crystal layer LC arranged between the common electrode 25 and the pixel electrodes 21. A laser beam output in a thickness direction of the diffraction grating layer 6 is modulated by the spatial light modulator SLM, passes therethrough, and is output to the outside.

Abstract: The coordinates of an unit configuration region R11 is (X1, Y1), and the coordinates of an unit configuration region Rmn is (Xm, Yn) (m and n are natural numbers). Rotation angles ? with respect to a center of apexes of an isosceles triangle are different according to coordinates, and at least three different rotation angles ? are contained in all of the photonic crystal layer.

Abstract: A metamaterial optical member 100 includes a light collecting optical member 1 having a light-entering surface IN1 and a light-exiting surface OUT1 and having a light collecting function and an antireflection film 2 disposed in the light-exiting surface OUT1 of the light collecting optical member 1. The antireflection film 2 has a first metamaterial structure in which a refractive index is gradually reduced in the light travelling direction. The metamaterial optical member 100 includes the antireflection film 2 having the metamaterial structure, thereby externally extracting light.

Abstract: This semiconductor laser device includes a semiconductor laser chip and a spatial light modulator SLM which is optically connected to the semiconductor laser chip. The semiconductor laser chip LDC includes an active layer 4, a pair of cladding layers 2 and 7 sandwiching the active layer 4, and a diffraction grating layer 6 which is optically connected to the active layer 4. The spatial light modulator SLM includes a common electrode 25, a plurality of pixel electrodes 21, and a liquid crystal layer LC arranged between the common electrode 25 and the pixel electrodes 21. A laser beam output in a thickness direction of the diffraction grating layer 6 is modulated and reflected by the spatial light modulator SLM and is output to the outside.

Abstract: This semiconductor laser device includes a semiconductor laser chip and a spatial light modulator SLM which is optically connected to the semiconductor laser chip. The semiconductor laser chip LDC includes an active layer 4, a pair of cladding layers 2 and 7 sandwiching the active layer 4, and a diffraction grating layer 6 which is optically connected to the active layer 4. The spatial light modulator SLM includes a transparent common electrode 25, a plurality of transparent pixel electrodes 21, a liquid crystal layer LC arranged between the common electrode 25 and the pixel electrodes 21. A laser beam output in a thickness direction of the diffraction grating layer 6 is modulated by the spatial light modulator SLM, passes therethrough, and is output to the outside.

Abstract: The coordinates of an unit configuration region R11 is (X1, Y1), and the coordinates of an unit configuration region Rmn is (Xm, Yn) (m and n are natural numbers). Rotation angles ? with respect to a center of apexes of an isosceles triangle are different according to coordinates, and at least three different rotation angles ? are contained in all of the photonic crystal layer.

Abstract: The coordinates of a unit configuration region R11 are (X1, Y1), and the coordinates of a unit configuration region Rmn are (Xm, Yn) (m and n are natural numbers). Rotational angles ? are different according to coordinates, and at least three different rotational angles ? are contained in all of the photonic crystal layer.

Abstract: A substrate 18, a cathode 20 and an anode 22 are stored in a space demarcated by a casing 10, and the space is evacuated. The cathode 20 and the anode 22 are provided on the same surface of a substrate 18 having electric insulation, and have a comb-tooth shape so as to be mutually engaged. Therefore, the area of the part in which the cathode 20 and the anode 22 approach each other becomes larger, and thereby photoelectrons discharged from the cathode 20 through the incidence of ultraviolet rays are transmitted in the vacuum, and are favorably collected in the anode 22.

Abstract: A substrate 18, a cathode 20 and an anode 22 are stored in a space demarcated by a casing 10, and the space is evacuated. The cathode 20 and the anode 22 are provided on the same surface of a substrate 18 having electric insulation, and have a comb-tooth shape so as to be mutually engaged. Therefore, the area of the part in which the cathode 20 and the anode 22 approach each other becomes larger, and thereby photoelectrons discharged from the cathode 20 through the incidence of ultraviolet rays are transmitted in the vacuum, and are favorably collected in the anode 22.