Lighting Apparatus with Wavelength-Separated Sensor for Gesture Control

The patent segments the lighting system into distinct functional modules: an illuminating unit with illumination light sources, a projection-type image display unit with image-projecting light sources, and a sensor unit. Each module operates independently with its own control, allowing versatile functionality while managing complexity through modular design. The wavelength separation further segments the optical paths to prevent interference between functions.

The lighting apparatus integrates multiple functions into a single device: general illumination, image projection, and gesture/sensor-based operation detection. This multi-functionality is achieved by combining different light sources (illumination and projection) and a sensor unit that detects operations in the image projection area, allowing the device to serve multiple purposes simultaneously or independently.

The patent applies local quality by assigning specific wavelength ranges to different functions: the sensor emits operation-detecting light in a wavelength range distinct from both the illumination light and image-projecting light. This localized wavelength allocation allows the sensor to detect gestures without interfering with illumination or projection functions, and enables precise control of light amounts for each function independently.

The control unit dynamically adjusts the light amount of operation-detecting light based on operational states. When the sensor is actively detecting operations, the operation-detecting light is emitted at appropriate intensities; when not in use, the light amount is reduced or turned off. This parameter adjustment optimizes interactive functionality while minimizing energy consumption and avoiding interference with other light sources.

The optical system is segmented into separate pathways: the projection optical system is optimized for image projection with appropriate lenses and focus mechanisms, while the illuminating unit has its own optical design for uniform light distribution. The sensor unit operates in a third optical pathway using wavelength discrimination. This segmentation allows each subsystem to be optimized for its specific function without compromising others.

The patent introduces wavelength as an intermediary parameter to separate the functions of illumination, projection, and sensing. By assigning distinct wavelength ranges to each function and using wavelength-selective optical elements, the system achieves high image projection quality through optimized projection optics while maintaining uniform illumination through dedicated illuminating optics that operate in separate wavelength bands.