A projection device includes: an illumination system providing an illumination beam; a light valve arranged on a transmission path of the illumination beam and converting the illumination beam into an image beam; a projection lens arranged on a transmission path of the image beam and projecting the image beam out of the projection device; a first actuating module connecting and moving a first element, so that the image beam shifts back and forth along at least one of the first, second, and third directions; and a second actuating module connecting and moving a second element, so that the image beam shifts back and forth along at least one of the first, second, and third directions. The first and second directions are perpendicular. The third and first directions form an angle of 45 degrees, so do the third and second directions. The first and second elements are different.

A projector includes a projection optical device configured to project image light and a moving device configured to move the projection optical device in a first direction crossing an incident direction of the image light on the projection optical device. The moving device includes a holding member configured to hold the projection optical device and a supporting member configured to support the holding member to be movable in the first direction. The projection optical device includes a lens barrel configured to hold a lens and a flange provided in the lens barrel and held by the holding member. The supporting member includes guide surfaces that guide the movement of the holding member in the first direction. The holding member includes contact surfaces that are in contact with the guide surfaces. The guide surfaces and the contact surfaces cross the incident direction.

A projection lens adjustment module applicable to a projection lens is provided. The projection lens includes a first assembly and a second assembly. The projection lens adjustment module includes a flexible connection line, an adjusting element and a driving mechanism. The flexible connection line has a first end and a second end opposite to each other. The adjusting element is connected to the first end. The driving mechanism is connected to the second assembly and the second end. When the adjusting element drives the first end to move along a first direction thereby leading the second end to move along a second direction non-parallel to the first direction, the second end drives the second assembly to move along an optical axis direction of the projection lens relative to the first assembly through the driving mechanism.

A projection lens has a lens barrel holding a lens. In a case where an image forming panel is disposed to be shifted with respect to an optical axis of the projection lens, in a second part on a side to which the image forming panel is shifted with respect to the optical axis of the projection lens, there is a great increase in temperature, and in a first part on the opposite side, there is a small increase in temperature. A lens barrel heating optical section has a first mirror, condensing lenses, and a second mirror. The lens barrel heating optical section emits the redundant light, which is reflected by the color wheel, toward the first part of the lens barrel. By heating the first part through redundant light, temperature distribution in the circumferential direction becomes uniform, and deterioration in performance of the projected image is suppressed.

A projection lens includes: first to fifth lenses; a light shielding ring; an aperture stop; and a lens barrel. The light shielding ring is rotated in a circumferential direction of the lens barrel by a rotation mechanism. In a case where an image forming panel is shifted with respect to an optical axis of the projection lens, a part, through which the light passes, is biased in the projection lens, whereby temperature distribution occurs in the lens barrel in the direction perpendicular to the optical axis. The thermal deformation of the high temperature side of the lens barrel due to the temperature distribution is greater than that on the low temperature side. The respective lenses may be tilted due to thermal deformation. By rotating the light shielding ring through the rotation mechanism, the temperature increases uniformly in the circumferential direction of the light shielding ring.

An adjustment support device includes: a processor configured to perform a control of: generating guide information indicating an operation method of an adjustment mechanism for adjusting inclination of a projection apparatus with respect to a reference surface based on inclination information indicating the inclination; and outputting the generated guide information

A projector used a projection lens to enlarge and project image light generated by image generator. When it is assumed that the on-optical-axis position of a lens surface where the maximum of light ray passage ranges (effective diameter) is minimized in the projection lens is a minimum diameter position, a stop is provided on a lens shifted from the minimum diameter position toward the light exiting side. The lens on which the stop is provided is a lens (for example, fourth lens closest to minimum diameter position) that satisfies 0.8φ.sub.1≦φ.sub.2≦φ.sub.1, where φ.sub.1 represents the light flux diameter on a surface where the on-axis light flux diameter is maximized, and φ.sub.2 is the diameter of the stop.

A projector of the present disclosure includes a light source that emits laser light, a metasurface element that modulates the phase of the laser light emitted from the light source, and a light modulation element that modulates the phase-modulated laser light emitted from the metasurface element to generate projection light.

A projector includes a base, an optical engine assembly, a lens assembly, a connector, and a buffer. The base includes a primary plate body and a first connection part connected to the primary plate body. The optical engine assembly is configured to provide an image beam. The lens assembly is arranged above the base and located on a transmission path of the image beam. The connector includes a first fixing part and a second connection part connected to the first fixing part. The first fixing part is fixed to the lens assembly, one of the first connection part and the second connection part is a slot, and the other is movably inserted into the slot. The buffer is arranged in the slot, and the first connection part is connected to the second connection part through the buffer. The projector may effectively prevent lens vibration.

A projection lens module includes a lens assembly, a reflector arranged beside the lens assembly, a housing assembly covering the reflector, and a buffer. The reflector includes a reflecting surface and a back surface opposite to each other; the reflecting surface faces the lens assembly to reflect a light beam passing through the lens assembly. The housing assembly includes a flow channel frame, an inner surface. The flow channel frame is arranged on the inner surface and protrudes toward the back surface. The buffer is sandwiched between the flow channel frame and the back surface. A flow channel is formed between the flow channel frame and the back surface and communicates with the air inlet and the air outlet.