Abstract: It is to provide an optical element, an optical module, an optical connector, and an optical module manufacturing method that can quickly and very accurately control the amount of outgoing light to a desired amount when incident light is outputted, reduce costs, and enhance manufacturing efficiency. A diffraction grating 9 having a periodic structure made from a plurality of grating grooves 10 and formed to allow control of an amount of outgoing light using polarization-dependent characteristics when incident light is outputted as the outgoing light and a mark 11 indicating at least one of either a grating groove 10 direction of the diffraction grating 9 or a periodic direction of the diffraction grating 9 are included.

Abstract: It is to provide an optical element, an optical module holder including the optical element, an optical module, and an optical connector that can attenuate with high accuracy an amount of light coupled between an optical transmission line and a photonic element using light refraction, thereby realizing appropriate optical communication while reducing manufacturing costs. A light attenuating refractive surface 7 is formed on an optical surface 4 disposed on an optical path between an optical transmission line 2 and a photonic element 3 in a main body of the optical element. The light attenuating refractive surface 7 attenuates the amount of light coupled between the optical transmission line 2 and the photonic element 3 by refracting and deflecting incident light.

Abstract: It is to provide an optical element, an optical module holder including the optical element, an optical module, and an optical connector that can attenuate with high accuracy an amount of light coupled between an optical transmission line and a photonic element using light refraction, thereby realizing appropriate optical communication while reducing manufacturing costs. A light attenuating refractive surface 7 is formed on an optical surface 4 disposed on an optical path between an optical transmission line 2 and a photonic element 3 in a main body of the optical element. The light attenuating refractive surface 7 attenuates the amount of light coupled between the optical transmission line 2 and the photonic element 3 by refracting and deflecting incident light.

Abstract: It is to provide an optical element, an optical module, an optical connector, and an optical module manufacturing method that can quickly and very accurately control the amount of outgoing light to a desired amount when incident light is outputted, reduce costs, and enhance manufacturing efficiency. A diffraction grating 9 having a periodic structure made from a plurality of grating grooves 10 and formed to allow control of an amount of outgoing light using polarization-dependent characteristics when incident light is outputted as the outgoing light and a mark 11 indicating at least one of either a grating groove 10 direction of the diffraction grating 9 or a periodic direction of the diffraction grating 9 are included.

Abstract: It is to provide an optical element, an optical pickup device, and an optical information recording and/or reproducing apparatus, which can decrease the offset effectively and detect fine tracking error signals even when there is a difference between the light quantities of the two sub-beams. The first to fifth periodic structures enable generation of three beams that can provide an ideal-shaped waveform of the sum signal of two sub push-pull signals which are detected respectively from two sub-beams, whether or not there is a difference between the light quantities of the two sub-beams.

Abstract: It is to provide an optical pickup device and an optical element, which can appropriately perform signal processing for a plurality of sets of light having different wavelength from each other by a single light receiving element, can cut the cost, and can widen versatility of possible design form. There are provided: a first and a second light sources for emitting first light and second light having different wavelengths; an optical information recording medium; an objective lens for concentrating a first and/or second light; an optical element which comprises an astigmatism generating structure for giving astigmatism to the first and second light, and a diffraction structure for diffracting at least either the first or the second light; and a light receiving element.