Abstract: An electrophotographic photoreceptor includes a conductive substrate, and a lamination type photosensitive layer disposed on the conductive substrate and including a charge generation layer and a charge transport layer, in which the charge transport layer contains a charge transport material, at least one of a polyester resin (PEz) or a polycarbonate resin (PCz) that has at least one of a structure (Z1) represented by Formula (Z1) or a structure (Z2) represented by Formula (Z2) at at least one terminal, and a resin (X) that has at least one of a unit (X1) represented by Formula (X1) or a unit (X2) represented by Formula (X2), a mass proportion of the resin (X) in a total amount of the polyester resin (PEz), the polycarbonate resin (PCz), and the resin (X) in the charge transport layer is 0.

Abstract: A method for measuring optical characteristics of a Mach-Zehnder type optical modulation device having an incident part, a waveguide for propagating light incident from the incident part, and a plurality of emitting parts each for emitting light. The method includes inputting light from a light source to the incident part of the optical modulation device through a first optical fiber, receiving emitted lights emitted from the plurality of emitting parts of the optical modulation device by a plurality of light receivers, obtaining a total value of currents by converting electric signals into currents and summing the currents, the electric signals being outputted by the plurality of light receivers receiving the emitted lights, and aligning the incident part of the optical modulation device and the first optical fiber based on the total value of currents.

Abstract: A method for measuring optical characteristics of a Mach-Zehnder type optical modulation device having an incident part, a waveguide for propagating a light incident from the incident part, and a plurality of emitting parts each for emitting the light. The method includes inputting a light from a light source to the incident part of the optical modulation device through a first optical fiber, receiving emitted lights emitted from the plurality of emitting parts of the optical modulation device by a plurality of light receiving parts, obtaining a total value of currents by converting electric signals into the currents and summing the currents, the electric signals being outputted by the plurality of light receivers in receiving the emitted lights, and aligning the incident part of the optical modulation device and the first optical fiber based on the total value.

Abstract: An optical modulator includes a substrate having a first face and a second face; an input port provided on the first face; a first waveguide provided on the substrate, the waveguide being connected to the input port; a first coupler provided on the substrate, the first coupler being optically connected to the first waveguide; an output port provided on the first face of the substrate, the output port being optically connected to the first coupler; and a first anti-reflection coating provided on the second face. The first face and the second face are arranged along a first direction. The first face and the second face extend in a direction intersecting the first direction. The first coupler extends in the first direction.

Abstract: An optical modulator includes a substrate having a first face and a second face; an input port provided on the first face; a first waveguide provided on the substrate, the waveguide being connected to the input port; a first coupler provided on the substrate, the first coupler being optically connected to the first waveguide; an output port provided on the first face of the substrate, the output port being optically connected to the first coupler; and a first anti-reflection coating provided on the second face. The first face and the second face are arranged along a first direction. The first face and the second face extend in a direction intersecting the first direction. The first coupler extends in the first direction.

Abstract: An optical fiber array includes a support, a single-mode optical fiber and a plurality of multimode optical fibers, the single-mode optical fiber and the multimode optical fibers being arranged on the support, and a polarizing plate provided on an end face of the support, wherein the single-mode optical fiber has polarization maintaining characteristics, an end face of the single-mode optical fiber and end faces of the multimode optical fibers face the end face of the support, and the polarizing plate covers the end faces of the multimode optical fibers.

Abstract: An optical fiber array includes: a support; a single-mode optical fiber and a plurality of multimode optical fibers, the single-mode optical fiber and the multimode optical fibers being arranged on the support; and a polarizing plate provided on an end face of the support, wherein the single-mode optical fiber has polarization maintaining characteristics, an end face of the single-mode optical fiber and end faces of the multimode optical fibers face the end face of the support, and the polarizing plate covers the end faces of the multimode optical fibers.