Disclosed is a thin film characteristic measuring apparatus, which is used for measuring the thickness or width of a thin film of an object to be examined. The thin film characteristic measuring apparatus comprises a light source, a first reflecting mirror, a first actuator and a lens assembly. The lens assembly is formed so that the angle formed by an optical axis and a chief ray of the rays transmitted through the lens assembly is less than or equal to the angle formed by the optical axis and a chief ray of the rays incident to the lens assembly. The light source can comprise superluminescent diodes (SLD). Provided is the thin film characteristic measuring apparatus, which enables the light transmitted through the lens assembly to reciprocate on an incident surface of the object to be examined while the first reflecting mirror repeatedly tilts within a predetermined angle range, and thus can accurately measure a relatively large area and can variously control a position to be measured, a method and the like.

A system and method for advanced lens geometry fitting is provided for projecting images using a projector with a non-planar lens. An initial estimate of intrinsic parameters of the projector can be determined, for example from a list; an initial estimate of extrinsic parameters of the projector can be determined based on the initial estimate of intrinsic parameters. The intrinsic parameters and extrinsic parameters can be optimized together by starting with a simple lens model and iteratively adding nonlinear terms, an error function evaluated at each iteration, for example for each set of intrinsic parameters in the list and the corresponding extrinsic parameters. As the values of the error function converges the optimized intrinsic parameters and the optimized extrinsic parameters can be used to generate images that are projected by the projector.

A lens module, comprising a first lens, a second lens and a third lens sequentially and coaxially arranged in the transmission direction of incident light. The first lens is a biconcave lens, the second lens is a meniscus lens, and the third lens is a biconvex lens. The first lens comprises a first curved surface and a second curved surface. The second lens comprises a third curved surface and a fourth curved surface. The third lens comprises a fifth curved surface and a sixth curved surface. The first to the sixth curved surfaces are sequentially arranged in the transmission of the incident light, and the curvature radii of the first to the sixth curved surfaces are sequentially −37±5%, 400±5%, −130±5%, −60±5%, 360±5%, and −68±5%, in a unit of millimeter. Due to the arrangement and parameter design of the first to the third lenses of the lens module, the 3D printer can achieve high machining precision. The present invention also provides a 3D printer and a 3D printing method thereof.

An Fθ lens and a laser processing device for far-infrared laser processing are provided. The Fθ lens for far-infrared laser processing comprises a first lens (L1), a second lens (L2) and a third lens (L3) which are coaxially arranged successively along a transmission direction of incident light beams, wherein the first lens is a negative meniscus lens, and the second lens and the third lens are positive meniscus lenses; and all the middle parts of the first lens, the second lens and the third lens protrude towards the transmission direction of incident light beams. The Fθ lens can improve the imaging quality and the resolution distance, effectively calibrate the astigmatism and distortion of the lens, reduce the influence of high-order aberrations, and has a high degree of energy concentration of laser focus points and high processing accuracy, thereby meeting the requirements for cutting or drilling. The Fθ lens is miniaturized, so that the volume of the lens is effectively controlled, and costs are reduced.

There are provided a lens, a method of fabricating the lens, and a light scanning unit. The lens includes a lens portion having an effective optical surface, and a gate-side flange portion between the lens portion and a gate-side end of the lens. If the lens is disposed between two polarizers configured to polarize light linearly in perpendicular directions and is illuminated in an optical axis direction, interference fringes are generated on the lens, and peripheral interference fringes of the interference fringes extend continuously from the gate-side end and are longer than the gate-side flange portion.

An apparatus and method for making a three-dimensional object from a solidifiable material using two photon absorption is described. The use of two photon absorption allows for the creation of a non-solidification zone beneath the exposed surface of a solidifiable material so that no separation is required between the most recently solidified layer of the object and a substrate such as a glass, a film, or a glass/film combination. In addition, when used with a linear scanning device, two photon absorption causes solidification to occur within a small spot area, which provides a means for creating larger, higher resolution objects than DLP systems or laser systems that use single photon absorption.

A method for designing freeform surface imaging system comprises: constructing a series of coaxial spherical systems with different optical power (OP) distributions; tilting all optical elements of each coaxial spherical system by a series of angles to obtain a series of off-axis spherical systems; finding all unobscured off-axis spherical systems; and then specifying a system size or structural constraints, and finding a series of compact unobstructed off-axis spherical systems; constructing a series of freeform surface imaging systems based on the series of compact unobstructed off-axis spherical system, and correcting the OP of entire system; improving an image quality of each freeform surface imaging systems and finding an optimal tilt angle of an image surface; and automatically evaluating an image quality of each freeform surface imaging system based on an evaluation metric, and outputting the freeform surface imaging systems that meet a given requirements.

An object is to provide a light deflection device having a simple structure suitable for reducing the size and weight where a deflection angle can be increased, and an optical device including the light deflection device. The light deflection device includes: a MEMS light deflection element that deflects incident light to be emitted; and an angle increasing optical element that is disposed downstream of the light deflection element in a light traveling direction and increases an angle range of a deflection angle of light emitted from the light deflection element, in which the MEMS light deflection element has a function of collecting and emitting incident light.

In a toric lens comprising a toric surface having a fine uneven structure, the fine uneven structure includes a plurality of holes, the plurality of holes have a hole depth H and a surface opening diameter φt which satisfy an expression of 0.3≤H/φt≤0.6, and (a) the plurality of holes have a hole structure having a cylindrical shape on a bottom surface side and a circular truncated cone shape having an opening diameter increasing toward a surface side, or (b) an angle θ formed between an opening portion and the surface of the plurality of holes satisfies 78°≤θ≤85°.

An optical system may include a first optical assembly and a first scan field expansion assembly. The first optical assembly may include or may be configured as a first flat-field lens. The first flat-field lens may have a first nominal scan field with a first flat focal plane. The first scan field expansion assembly may include one or more first field-expanding optical elements configured to provide a first expanded scan field coinciding with the first flat focal plane. The first expanded scan field may have a cross-sectional width and/or area that exceeds a corresponding cross-sectional width and/or area of the first nominal scan field. A method of additively manufacturing a three-dimensional object may include directing a first energy beam through the first optical assembly, and directing the first energy beam through the first scan field expansion assembly.