An approach for projecting light may be implemented using a acousto-optical depth switch that uses surface acoustic waves produced along a substrate to guide image light to different areas. The surface acoustic waves may be generated on a substrate using a transducer. Surface acoustic waves of different frequencies can guide image light onto different optical elements at different physical positions. The optical elements may be configured to show objects in an image at different distances from a viewer.

An approach for projecting light may be implemented using a acousto-optical depth switch that uses surface acoustic waves produced along a substrate to guide image light to different areas. The surface acoustic waves may be generated on a substrate using a transducer. Surface acoustic waves of different frequencies can guide image light onto different optical elements at different physical positions. The optical elements may be configured to show objects in an image at different distances from a viewer.

An approach for projecting light may be implemented using a acousto-optical depth switch that uses surface acoustic waves produced along a substrate to guide image light to different areas. The surface acoustic waves may be generated on a substrate using a transducer. Surface acoustic waves of different frequencies can guide image light onto different optical elements at different physical positions. The optical elements may be configured to show objects in an image at different distances from a viewer.

A light source unit mountable to an image display apparatus for irradiating scan light to an optical scanning system to generate an image includes a plurality of light emitters to emit corresponding lights having different wavelengths, a plurality of coupling lenses respectively disposed for the plurality of light emitters to respectively pass through the lights emitted from the plurality of light emitters, and a plurality of aperture-formed members respectively disposed for the plurality of coupling lenses to respectively pass through the lights coming from the coupling lenses, each of the plurality of aperture-formed members formed of an aperture having an aperture size set differently depending on the wavelengths of the lights emitted from the plurality of light emitters.

A light source unit mountable to an image display apparatus for irradiating scan light to an optical scanning system to generate an image includes a plurality of light emitters to emit corresponding lights having different wavelengths, a plurality of coupling lenses respectively disposed for the plurality of light emitters to respectively pass through the lights emitted from the plurality of light emitters, and a plurality of aperture-formed members respectively disposed for the plurality of coupling lenses to respectively pass through the lights coming from the coupling lenses, each of the plurality of aperture-formed members formed of an aperture having an aperture size set differently depending on the wavelengths of the lights emitted from the plurality of light emitters.

A scanning projector and method is provided that generates a feedback signal from at least one photodetector. In the scanning projector, a scanning mirror is configured to reflect laser light into an image region and an over scanned region. The at least one photodetector is configured to receive a portion of the reflected laser light impacting the over scanned region, and provides the feedback signal responsive to the received portion of light. This feedback signal can then be used to provide precise control of the scanning mirror.

A scanning projector and method is provided that generates a feedback signal from at least one photodetector. In the scanning projector, a scanning mirror is configured to reflect laser light into an image region and an over scanned region. The at least one photodetector is configured to receive a portion of the reflected laser light impacting the over scanned region, and provides the feedback signal responsive to the received portion of light. This feedback signal can then be used to provide precise control of the scanning mirror.

A scanning projector and method is provided that generates a feedback signal from at least one photodetector. In the scanning projector, a scanning mirror is configured to reflect laser light into an image region and an over scanned region. The at least one photodetector is configured to receive a portion of the reflected laser light impacting the over scanned region, and provides the feedback signal responsive to the received portion of light. This feedback signal can then be used to provide precise control of the scanning mirror.

A scanning projector and method is provided that generates a feedback signal from at least one photodetector. In the scanning projector, a scanning mirror is configured to reflect laser light into an image region and an over scanned region. The at least one photodetector is configured to receive a portion of the reflected laser light impacting the over scanned region, and provides the feedback signal responsive to the received portion of light. This feedback signal can then be used to provide precise control of the scanning mirror.

A light flux diameter expanding element (a pupil expanding element) used in a retina scanning display device includes first to fourth diffraction gratings which are provided with grating patterns extending in a first direction, and fifth to eighth diffraction gratings which are provided with grating patterns extending in a second direction, and includes a half-wave plate between the first diffraction grating and the fifth diffraction grating. A first light flux of polarized light in which an electric field vector oscillates in the first direction enters the first diffraction grating. A second light flux of polarized light in which the electric field vector oscillates in the second direction enters the fifth diffraction grating due to the half-wave plate. Therefore, it is possible to expand a diameter of the incident first light flux in the first direction and the second direction and emit the result as the third light flux.