Abstract: To provide an optical 90-degree hybrid formed of a silicon waveguide capable of suppressing an optical loss and a phase error, and facilitating electronic packaging and optical packaging. In the optical 90-degree hybrid circuit including two optical branching units facing each other and two optical coupling units facing away from each other, four arm waveguides are arranged including bent waveguides each of which guides an output light of the optical branching unit to the optical coupling unit, and is formed in a curved shape.

Abstract: A liquid ejecting head of a side shooter type includes a plate including a plurality of nozzles arranged along a first direction and an actuator with a plurality of pressure chambers arranged along the first direction. Each pressure chamber communicates with a corresponding one of the nozzles. The actuator further includes dummy chambers, each of which is between two otherwise adjacent pressure chambers. Common chambers are provided in the actuator. The pressure and dummy chambers are arranged between the common chambers. The end portions of the pressure chambers are connected to a common chamber. The width of the end portions of each of the pressure chambers is less than the width of a portion of the pressure chamber between the end portions.

Abstract: According to one embodiment, a liquid ejection head includes an actuator with a plurality of pressure chambers and dummy chambers. The pressure chambers are each part of a groove that is disposed between an adjacent pair of sidewalls. Each pressure chamber is in fluid communication with a nozzle for ejecting a liquid. The dummy chambers are each between an adjacent pair of pressure chambers. A common chamber is fluidly connected to an end of each of the pressure chambers. A throttle portion is at the end portion of each pressure chamber. Each throttle portion blocks a part of a liquid flow path from the first common chamber to the pressure chamber. The first throttle portion is formed of a resin material.

Abstract: A liquid ejecting head of a side shooter type includes a plate including a plurality of nozzles arranged along a first direction and an actuator with a plurality of pressure chambers arranged along the first direction. Each pressure chamber communicates with a corresponding one of the nozzles. The actuator further includes dummy chambers, each of which is between two otherwise adjacent pressure chambers. Common chambers are provided in the actuator. The pressure and dummy chambers are arranged between the common chambers. The end portions of the pressure chambers are connected to a common chamber. The width of the end portions of each of the pressure chambers is less than the width of a portion of the pressure chamber between the end portions.