Abstract: Provided are a diffusion plate that diffuses light emitted from a light source, and a prism having a first surface to receive the light transmitted through the diffusion plate, a second surface to reflect the light in contact with a measurement target liquid, and a third surface to extract the reflected light. The light source, the diffusion plate, a light receiving lens, and an imaging element are accommodated in a holder that presses the prism from the inner side to the outer side.

Abstract: Provided is a displacement sensor having a modular structure that allows further downsizing. A housing of a head is made up of a main housing and a lid member, both of which are precision molded products made of a metal material. A first holder to which a light projector is bonded and a second holder to which a light receiver is bonded are individually positioned on and bonded to the lid member. This work is performed by a mounting device. Optical components such as a light projecting lens are also bonded to the lid member, and the lid member modularized by incorporating such optical components is assembled and welded to the main housing.

Abstract: There is provided a photoelectric switch capable of reducing a size of a whole device while suppressing light amount irregularity and color irregularity of detected light. The photoelectric switch includes: a surface mount LED, configured to generate a light containing a plurality of color components with different hues; an optical shield disposed between the surface mount LED and a light projecting lens to shield the light around an optical opening passing the light from the surface mount LED to the light projecting lens; a light receiving element configured to selectively receive the light to generate a plurality of light reception signals; a controller configured to control a light projecting amount of the surface mount LED based on the light reception signal.

Abstract: There is provided a photoelectric switch capable of reducing a size of a whole device while suppressing light amount irregularity and color irregularity of detected light. The photoelectric switch includes: a surface mount LED, configured to generate a light containing a plurality of color components with different hues; an optical shield disposed between the surface mount LED and a light projecting lens to shield the light around an optical opening passing the light from the surface mount LED to the light projecting lens; a light receiving element configured to selectively receive the light to generate a plurality of light reception signals; a controller configured to control a light projecting amount of the surface mount LED based on the light reception signal.