Projection systems and/or methods for efficient use of light by recycling a portion of the light energy for future use are disclosed. In one embodiment, a projection display system is disclosed comprising a light source; an integrating rod that receives light from said light source at a proximal end that comprise a reflective surface which may reflecting/recycle light down said integrating rod; of reflecting light down said integrating rod; a relay optical system, said relay optical system further comprising optical elements that are capable of moving the focal plane of the projector display system; and a modulator comprising at least one moveable mirror that reflects light received from the integrating rod in either a projection direction or a light recycling direction.

A lighting apparatus for a vehicle may include a light output unit; an interface unit; and at least one processor. The at least one processor may be configured to control the light output unit to generate light that illuminates an exterior of the vehicle. The at least one processor may also be configured to receive first information via the interface unit; and control the light output unit to display, via the light that illuminates the exterior of the vehicle, a visual image corresponding to the received first information. The at least one processor may further be configured to receive second information via the interface unit; and control the light output unit based on the received second information to change the visual image displayed by the light that illuminates the exterior of the vehicle.

An image projector with a high optical efficiency projects an image at an arbitrary distance from an observer. The image projector includes an illumination module having at least one spatially coherent light source; a phase image generator with an array of optical phase shifting elements; an electronic image controller connected electrically to the phase image generator; and a waveguide which includes at least one embedded partial reflector. The waveguide may be positioned either between the illumination module and the waveguide, or between the waveguide and the observer. The phase image generator may include phase shifts for canceling speckle, correcting optical aberrations, and/or compensating interference caused by light rays having different optical path lengths.

A projection device, including an illumination light source, an electrochromic module, at least one light valve, and a projection lens, is provided. The illumination light source provides an illumination beam. The electrochromic module is disposed on a transmission path of the illumination beam. The electrochromic module includes at least one electrochromic element, and sequentially maintains or changes a wavelength of the illumination beam penetrating the at least one electrochromic element. The at least one light valve is disposed on the transmission path of the illumination beam transmitted by the electrochromic module to convert the illumination beam into an image beam. The projection lens is disposed on a transmission path of the image beam to project the image beam out of the projection device. The projection device and the use method thereof provided by the disclosure may change the color light output or the color space of a display image.

A signal detection device of the present invention includes a first control unit configured to determine whether there are inputs of a plurality of external signals connected thereto, a second control unit configured to be activated after the first control unit is activated, a first input unit connected directly to the first control unit and configured to input a first external signal, which is one type of the plurality of external signals, and a second input unit connected to the first control unit via the second control unit and configured to input a second external signal, which is another type of the plurality of external signals, and the first control unit determines whether there is an input of the first external signal before the second control unit is activated and determines whether there is an input of the second external signal after the second control unit is activated.

A color wheel phase detection method and system, and a projection device. The phase detection system comprises a color wheel (1), a color wheel motor (2) that drives the color wheel (1) to rotate, and a control circuit (3); the color wheel motor (2) is a three-phase motor, and the control circuit (3) comprises a three-phase driving circuit (31) for driving the color wheel motor (2) to operate. The phase detection system further comprises a phase detection device (4) for detecting the three-phase driving circuit (31); when detecting a preset phase, the phase detection device (4) sends a pulse signal to the control circuit (3) to implement color wheel phase detection. Therefore, the effects of low costs, high accuracy, and high reliability are achieved.

An illumination system is adapted to provide an illumination light beam. The illumination system includes a light-source module and a light-shape adjustment module. The light-source module is adapted to emit a first light beam. The light-shape adjustment module is disposed on the transmission path of the first light beam and is adapted to adjust the light shape of the first light beam. The light-shape adjustment module includes a first light-diffusing element, a second light-diffusing element, and a first lens element. The first light beam sequentially passes through the first light-diffusing element, the first lens element, and the second light-diffusing element to form the illumination light beam. A projection device having the illumination system is also provided.

A light source module including first and second light sources, first and second wavelength conversion units, first and second light-splitting units is provided. The first light source emits a first light having a first wavelength. The first wavelength conversion unit converts at least one portion of the first light into a first converted light having a second wavelength. The second light-splitting unit allows the light having the first wavelength to travel through and reflects the light having the second wavelength. The second light source emits a second light having the first wavelength. The second wavelength conversion unit converts at least one portion of the second light into a second converted light having the second wavelength. The first light-splitting unit disposed between the first and the second wavelength conversion units reflects the light having the first wavelength and allow the light having the second wavelength to travel through.

An illumination system, an illumination control method and a projection apparatus are provided. The illumination system includes a first laser light source providing a first laser beam, and a light splitting module. When the first laser beam is incident to the light splitting module, a first portion of the first laser beam penetrates through the light splitting module, a second portion is reflected by the light splitting module. In the first illumination mode, the first laser beam is incident to the first light splitting region to form a first proportion of the first portion and the second portion. In the second illumination mode, the first laser beam is incident to the first light splitting region to form a second proportion of the first portion and the second portion, wherein the first proportion and the second proportion are different.

An illumination system includes an excitation light source, a first variable focus lens, a second variable focus lens, and a control unit. The excitation light source is adapted to provide an excitation light beam. The first variable focus lens is disposed on a transmission path of the excitation light beam. The first variable focus lens is located between the excitation light source and the second variable focus lens. The second variable focus lens is adapted to receive the excitation light beam exited from the first variable focus lens. The control unit is electrically connected to the first variable focus lens and the second variable focus lens, and is adapted to synchronously adjust focal lengths of the first variable focus lens and the second variable focus lens. A projection device including the above-mentioned illumination system of the invention is further provided.