A holographic projection operating device, holographic projection device and holographic optical module thereof are illustrated. The holographic optical module has a first and a second prism array. The first prism array has a plurality of first prisms with first faces in contact with each other to form a first optical interface. The second prism array has a plurality of second prisms with second faces in contact with each other to form a second optical interface. Light is incident on the first optical interface at a first incident angle to undergo total internal reflection and generate a first reflected ray or at a second incident angle to undergo total internal reflection and generate a second reflected ray. The first or second reflected ray enters the second prism array and hits the second optical interface at a third incident angle to undergo total internal reflection and generate a third reflected ray.

A holographic projection operating device, holographic projection device and holographic optical module thereof are illustrated. The holographic optical module has a first and a second prism array. The first prism array has a plurality of first prisms with first faces in contact with each other to form a first optical interface. The second prism array has a plurality of second prisms with second faces in contact with each other to form a second optical interface. Light is incident on the first optical interface at a first incident angle to undergo total internal reflection and generate a first reflected ray or at a second incident angle to undergo total internal reflection and generate a second reflected ray. The first or second reflected ray enters the second prism array and hits the second optical interface at a third incident angle to undergo total internal reflection and generate a third reflected ray.

An optical scanning apparatus used for detecting an object by irradiating light and receiving the reflected light including: a deflector; a light source having a first light-emitting unit that emits a first light and a second light-emitting unit that emits a second light having optical characteristics different from that of the first light; a first optical element disposed so that the first light emitted from the first light-emitting unit is incident thereon and reflects the first light and causes it to be incident on the deflector; a second optical element disposed so that the second light emitted from the second light-emitting unit is incident thereon and reflects the second light and causes it to be incident on the deflector; where the first optical element reflects the first light and transmits the second light, and where the second optical element reflects the second light and transmits the first light.

An optical scanning apparatus used for detecting an object by irradiating light and receiving the reflected light including: a deflector; a light source having a first light-emitting unit that emits a first light and a second light-emitting unit that emits a second light having optical characteristics different from that of the first light; a first optical element disposed so that the first light emitted from the first light-emitting unit is incident thereon and reflects the first light and causes it to be incident on the deflector; a second optical element disposed so that the second light emitted from the second light-emitting unit is incident thereon and reflects the second light and causes it to be incident on the deflector; where the first optical element reflects the first light and transmits the second light, and where the second optical element reflects the second light and transmits the first light.

A coaxial photoelectric sensor may include both an optical emitter and optical receiver disposed on a printed circuit board. A total internal reflection optical component may be optically aligned with the optical emitter so as to reflect an illumination signal generated by the emitter. A reflective optical component may be optically aligned with the total internal reflection optical component so as reflect the illumination signal received from the total internal reflection optical component. A target reflector component may be optically aligned with the reflective optical component to coaxially reflect the illumination signal received from the reflective optical component. An optical detector may be configured to generate an electrical signal in response to receiving the illumination signal.

A coaxial photoelectric sensor may include both an optical emitter and optical receiver disposed on a printed circuit board. A total internal reflection optical component may be optically aligned with the optical emitter so as to reflect an illumination signal generated by the emitter. A reflective optical component may be optically aligned with the total internal reflection optical component so as reflect the illumination signal received from the total internal reflection optical component. A target reflector component may be optically aligned with the reflective optical component to coaxially reflect the illumination signal received from the reflective optical component. An optical detector may be configured to generate an electrical signal in response to receiving the illumination signal.

An optical system may include a light source to provide a beam of light. The optical system may include a reflector to receive and redirect the beam of light. The optical system may include a light gate having an opening to permit the beam of light, from the reflector, to travel through the opening. The optical system may include a light sensor to receive a portion of the beam of light after the beam of light travels through the opening, and convert the portion of the beam of light to a signal. The optical system may include a processing device to determine whether a notch of a wafer is in an allowable position based on the signal.

An optical sensor includes a light source, a light receiver, and a convex portion. The light source emits light to an object. The light receiver receives reflected light of the emitted light reflected by an object and generates a signal showing a light reception result. The convex portion has a height higher than a height of the light source and the light receiver. The convex portion is between the light source and the light receiver to block reflected light from the light receiver when light from the light source is reflected within a range of a predetermined distance from the convex portion. The light receiver outputs a signal to show a light reception result of equal to or less than a threshold amount of light indicating that the reflected light is not received in response to proximity of the object being within a range of a predetermined distance.

An optical sensor includes a light source, a light receiver, and a convex portion. The light source emits light to an object. The light receiver receives reflected light of the emitted light reflected by an object and generates a signal showing a light reception result. The convex portion has a height higher than a height of the light source and the light receiver. The convex portion is between the light source and the light receiver to block reflected light from the light receiver when light from the light source is reflected within a range of a predetermined distance from the convex portion. The light receiver outputs a signal to show a light reception result of equal to or less than a threshold amount of light indicating that the reflected light is not received in response to proximity of the object being within a range of a predetermined distance.

A system, method and mirror are provided in order to more reliably detect the presence of an object, such as a person. In the context of a system, the system includes a sensor configured to emit signals having a predefined wavelength and to detect a reflection of the signals having the predefined wavelength. The system also includes a reflective panel positioned relative to the sensor such that the signals emitted by the sensor are directed toward the reflected panel. The system further includes a filter associated with the reflective panel and positioned relative to the sensor such that the signals emitted by the sensor are also directed toward the filter. The filter is configured to attenuate at least signals having the predefined wavelength.