A wavefront sensor includes a splitting element configured to split an incident light beam into a plurality of light beams, an image sensor configured to receive the plurality of light beams, and a processing unit configured to calculate a wavefront of the incident light beam based on an intensity distribution of the plurality of light beams received by the image sensor. The splitting element is either in direct contact with the image sensor or in contact with the image sensor via a plate glass. In the calculation of the wavefront, the processing unit corrects a relative positional deviation between the splitting element and the image sensor by calculating a rotation about a rotation axis.

A projection lens system that projects an image of a reduction side into a magnification side includes a diaphragm, a plurality of positive lenses, and a plurality of negative lenses. The plurality of positive lenses include a first positive lens closer to the magnification side than the diaphragm is and closest to the diaphragm, a second positive lens second closest to the diaphragm after the first positive lens on the magnification side, a third positive lens closer to the reduction side than the diaphragm is and closest to the diaphragm. The plurality of negative lenses include a first negative lens closer to the magnification side than the diaphragm is and closest to the diaphragm, and a second negative lens closer to the reduction side than the diaphragm is and closest to the diaphragm. The lenses have transmittances larger than threshold values, respectively.

A projection lens system that projects an image of a reduction side into a magnification side includes a diaphragm, a plurality of positive lenses, and a plurality of negative lenses. The plurality of positive lenses include a first positive lens closer to the magnification side than the diaphragm is and closest to the diaphragm, a second positive lens second closest to the diaphragm after the first positive lens on the magnification side, a third positive lens closer to the reduction side than the diaphragm is and closest to the diaphragm. The plurality of negative lenses include a first negative lens closer to the magnification side than the diaphragm is and closest to the diaphragm, and a second negative lens closer to the reduction side than the diaphragm is and closest to the diaphragm. The lenses have transmittances larger than threshold values, respectively.

A storage medium stores correction data for obtaining a correction amount for correcting image data, obtained from an image formed by a lens apparatus, with respect to a distribution of a light amount in the image, wherein the correction data includes a coefficient of an n-th order polynomial (where n is a non-negative integer) with respect to an image height h, the coefficient corresponding to a state of the lens apparatus. The coefficient satisfies a first inequality
−0.15≤dD′(h)−dDlens(h)≤1.98, where dDlens(h) represents a change amount of the light amount at the image height h per an increase amount dh of the image height h, and dD′(h) represents a change amount of an inverse of a value of the n-th order polynomial at the image height h per the increase amount dh.

A storage medium stores correction data for obtaining a correction amount for correcting image data, obtained from an image formed by a lens apparatus, with respect to a distribution of a light amount in the image, wherein the correction data includes a coefficient of an n-th order polynomial (where n is a non-negative integer) with respect to an image height h, the coefficient corresponding to a state of the lens apparatus. The coefficient satisfies a first inequality
−0.15≤dD′(h)−dDlens(h)≤1.98, where dDlens(h) represents a change amount of the light amount at the image height h per an increase amount dh of the image height h, and dD′(h) represents a change amount of an inverse of a value of the n-th order polynomial at the image height h per the increase amount dh.

A projection lens includes a plurality of lens units, and a diaphragm, wherein in a case where a lens unit that moves in an optical axis direction of the projection lens during focusing serves as a focus lens unit among the plurality of lens units, at least one lens included in a lens unit that is different from the focus lens unit among the plurality of lens units and is disposed more towards a reduction conjugate side than the diaphragm is configured to move in the optical axis direction when an amount of field curvature is adjusted to focus on a curved projection surface, and wherein when the amount of field curvature is adjusted, both the at least one lens and the focus lens unit move in the optical axis direction.

A projection lens includes a plurality of lens units, and a diaphragm, wherein in a case where a lens unit that moves in an optical axis direction of the projection lens during focusing serves as a focus lens unit among the plurality of lens units, at least one lens included in a lens unit that is different from the focus lens unit among the plurality of lens units and is disposed more towards a reduction conjugate side than the diaphragm is configured to move in the optical axis direction when an amount of field curvature is adjusted to focus on a curved projection surface, and wherein when the amount of field curvature is adjusted, both the at least one lens and the focus lens unit move in the optical axis direction.

A vehicular camera assembly includes an imager printed circuit board (imager PCB) having an imager disposed at a first side of the imager PCB. A lens barrel accommodates a lens and has an inner end. The inner end of the lens barrel is disposed at a first portion of a camera housing. The imager PCB is attached at a second portion of the camera housing that joins with the first portion so that the imager faces the lens. The second portion is adjustable relative to the first portion to align the imager and the lens. With the second portion engaging the first portion and the imager and lens aligned, a weld washer is laser welded to the first and second portions to join the second portion to the first portion.

The present invention relates generally to a head-mounted projection display, and more particularly, but not exclusively to a polarized head-mounted projection display including a light engine and a compact, high-performance projection lens for use with reflective microdisplays.

The present invention relates generally to a head-mounted projection display, and more particularly, but not exclusively to a polarized head-mounted projection display including a light engine and a compact, high-performance projection lens for use with reflective microdisplays.