An example includes a system, having: an illumination source configured to produce illumination light; and a spatial light modulator (SLM) optically coupled to the illumination source, the SLM comprising an array of picture elements. The SLM is configured to: receive the illumination light; direct, by a first portion of the picture elements, on state light in a first direction; and direct, by a second portion of the picture elements, off state light in a second direction. The example system includes imaging optics optically coupled to the SLM, the imaging optics configured to receive the on state light from the SLM and to project an image as an image portion of a beam; and non-imaging optics optically coupled to the SLM, the non-imaging optics configured to receive the off state light from the SLM and to project the off state light as part of the beam.

The invention provides a wide-aperture spherical primary mirror off-axis afocal optical system, including a primary mirror, a secondary mirror and an aberration compensation mirror group. The primary mirror is a spherical reflector, the secondary mirror are higher-order aspherical reflectors. The primary mirror and the secondary mirror form an off-axis two-mirror system to compress the beam aperture. The aberration compensation mirror group is a coaxial reflective system that is used off-axis. The aberration compensation mirror group has focal power to produce compensation aberrations. The incident beam passes through and is reflected by the primary mirror and secondary mirror sequentially and enters the aberration compensation mirror group thereafter. A spherical reflector is used as the primary mirror, which significantly reduces the development and manufacture cost of the system, and an aberration compensation mirror group is used off-axis to correct residual aberration in the system, which effectively improves imaging quality of the system.

Imaging systems and methods are provided for taking high-magnification photographs confined to a small physical volume. In some embodiments the system is composed of at least one lens, one or more partially reflective elements, and a sensor. The partial reflectors reflect a portion of the light back and forth between them to allow a long path length for a portion of the light from the lens to the sensor which enables a high magnification.

An optical system includes a lens having a first transmission surface, a reflection surface disposed on an enlargement side of the first transmission surface, and a second transmission surface disposed on the enlargement side of the reflection surface. The lens is made of resin. The reflection surface has a concave shape. A conditional expression below is satisfied,
10≤q×Fno/f.sup.2≤2989
where Fno is an F-number of the optical system, f is a focal length of the optical system, and q is an amount of light in an enlargement-side conjugate plane.

A lens has a first transmissive surface, a reflective surface, and a second transmissive surface sequentially arranged from a demagnifying side toward a magnifying side. The first transmissive surface and the reflective surface are located at the lower side of an imaginary axis extending in an axis-Z direction, and the second transmissive surface is located at the upper side of the imaginary axis. The reflective surface has a concave shape, and the second transmissive surface has a convex shape protruding toward the magnifying side. An imaginary line that connects an upper intersection to a lower intersection inclines with respect to an imaginary vertical line perpendicular to the imaginary axis in a plane YZ.

Imaging systems and methods are provided for taking high-magnification photographs confined to a small physical volume. In some embodiments the system is composed of at least one lens, one or more partially reflective elements, and a sensor. The partial reflectors reflect a portion of the light back and forth between them to allow a long path length for a portion of the light from the lens to the sensor which enables a high magnification.

An optical system includes a lens having a first transmission surface, a reflection surface disposed on an enlargement side of the first transmission surface, and a second transmission surface disposed on the enlargement side of the reflection surface. The lens is made of resin. The reflection surface has a concave shape. A conditional expression below is satisfied,

10≤q×Fno/f.sup.2≤2989

where Fno is an F-number of the optical system, f is a focal length of the optical system, and q is an amount of light in an enlargement-side conjugate plane.

A projection exposure method for exposing a radiation-sensitive substrate with at least one image of a pattern of a mask is provided in which an illumination field of the mask is illuminated by illumination radiation with an operating wavelength λ that was provided by an illumination system.

A detachable optical structure for a device having one or more cameras, where the detachable optical structure comprises a body having a transparent portion, and an optical element attached to the body. The optical element comprises a first aperture, a second aperture and two or more reflective elements arranged for parallel displacement of an optical axis from the first aperture to the second aperture. When the detachable optical structure is applied to the device, the optical element positions such that the first aperture is aligned with a camera of the device, and the optical element is at least partially aligned with the transparent portion of the body.

An optical system includes a first optical element including a first reflective area having a convex shape toward a magnification side, a second optical element including a second reflective area having a convex shape toward the magnification side, and a light shielding member disposed between the first optical element and the second optical element. Light from the magnification side travels to a reduction side through the second reflective area, the first reflective area, and a refractive area of the second optical element in order. The light shielding member is disposed between light entering the second reflective area and light entering the first reflective area in a first cross-section including an optical axis.