Abstract: An actuator is configured to drive an imaging lens system. The actuator includes a frame portion configured to accommodate the imaging lens system, a supporting portion disposed on the frame portion, a driving portion configured to drive the imaging lens system to move, an optical mark structure disposed on part of the frame portion, the supporting portion or the driving portion and a liquid disposed on the optical mark structure. The supporting portion is configured to support the imaging lens system and give the imaging lens system a degree of freedom of movement with respect to the frame portion. The optical mark structure includes a plurality of optical mark units arranged side by side. The liquid is in physical contact with the imaging lens system, the frame portion, the supporting portion or the driving portion that is adjacent to the optical mark structure.

Abstract: A plastic lens element includes an optical effective portion and a peripheral portion. The peripheral portion surrounds the optical effective portion and includes a peripheral surface and an optical inspecting structure. The optical inspecting structure is disposed between the optical effective portion and the peripheral surface and includes a first optical inspecting surface and a second optical inspecting surface. The first optical inspecting surface and the second optical inspecting surface are disposed on two sides of the peripheral portion respectively and correspond to each other.

Abstract: An actuator is configured to drive an imaging lens system. The actuator includes a frame portion configured to accommodate the imaging lens system, a supporting portion disposed on the frame portion, a driving portion configured to drive the imaging lens system to move, an optical mark structure disposed on part of the frame portion, the supporting portion or the driving portion and a liquid disposed on the optical mark structure. The supporting portion is configured to support the imaging lens system and give the imaging lens system a degree of freedom of movement with respect to the frame portion. The optical mark structure includes a plurality of optical mark units arranged side by side. The liquid is in physical contact with the imaging lens system, the frame portion, the supporting portion or the driving portion that is adjacent to the optical mark structure.

Abstract: An imaging lens system has an optical axis. The imaging lens system includes a plurality of optical elements, a lens barrel, an optical mark structure and a curable liquid. The optical elements are arranged along the optical axis. The lens barrel surrounds the optical axis, and at least one of the optical elements is accommodated in the lens barrel. The optical mark structure is disposed on the lens barrel, and the optical mark structure includes a plurality of optical mark units arranged side by side along a circumference direction that surrounds the optical axis. The curable liquid is disposed on the optical mark structure. The curable liquid is in physical contact with at least one of the optical mark units, and one of the optical elements adjacent to the optical mark structure is fixed to the lens barrel while the curable liquid is cured.

Abstract: A plastic lens element includes an optical effective portion and a peripheral portion. The peripheral portion surrounds the optical effective portion and includes a peripheral surface and an optical inspecting structure. The optical inspecting structure is disposed between the optical effective portion and the peripheral surface and includes a first optical inspecting surface and a second optical inspecting surface. The first optical inspecting surface and the second optical inspecting surface are disposed on two sides of the peripheral portion respectively and correspond to each other.

Abstract: A projector, a light source controller, and a light source control method are provided. The projector includes a light source, a wavelength conversion device, and a light source controller. The light source is adapted to provide a light beam. The wavelength conversion device is adapted to convert a wavelength of the light beam into a plurality of converted wavelengths. The light source controller includes a controller and a selector. The controller is adapted to receive a synchronization signal, and generate an enable signal and a plurality of indication signals according to the synchronization signal. The enable signal has a plurality of pulses, and there is an interval time between adjacent two pulses. The selector is adapted to select one of the control voltages according to the enable signal and the indication signals to generate a light source control signal.

Abstract: An autofocus method for a projector is provided. A projection lens of the projector projects at least projecting one image. The image includes a correction image. The projection lens has a focal length. The autofocus method includes: projecting the correction image; capturing the correction image; capturing a luminance parameter value of the correction image; controlling the focal length of the projection lens according to the luminance parameter value, wherein a process of controlling the focal length of the projection lens according to the luminance parameter value comprises a coarse adjustment phase and a fine adjustment phase, and the luminance parameter value changes with the adjustment of the focal length of the projection lens; and finding a maximum of the luminance parameter value. An autofocus system and a projector having the autofocus system are also provided.

Abstract: A projector, a light source controller, and a light source control method are provided. The projector includes a light source, a wavelength conversion device, and a light source controller. The light source is adapted to provide a light beam. The wavelength conversion device is adapted to convert a wavelength of the light beam into a plurality of converted wavelengths. The light source controller includes a controller and a selector. The controller is adapted to receive a synchronization signal, and generate an enable signal and a plurality of indication signals according to the synchronization signal. The enable signal has a plurality of pulses, and there is an interval time between adjacent two pulses. The selector is adapted to select one of the control voltages according to the enable signal and the indication signals to generate a light source control signal.