A method for determining an optical lens adapted for a wearer and optimized for at least a given optical criterion having a target value around a specific gaze direction. The method includes determining an intermediate optical lens by optimizing, using an optimization function, an initial optical lens so that the difference between the value of the at least given optical criterion of the intermediate optical lens and the target value of gaze directions around a specific gaze direction is smaller than or equal to a threshold value, and determining the optical lens by optimizing the intermediate optical lens so as to obtain the largest zone of gaze directions around the specific gaze direction for which the difference between the value of the at least given optical criterion and the target value around the specific gaze direction is smaller than or equal to the threshold value.

A projection system includes a first optical system and a second optical system disposed on an enlargement side of the first optical system. The first optical system includes a first lens group having positive power, a second lens group disposed on the enlargement side of the first lens group and having negative power, and an optical path deflector disposed between the first lens group and the second lens group. The second optical system includes a reflection member having a concave reflection surface. The second lens group includes three aspherical lenses. Conditional Expression (1) below is satisfied,

0.25<|F|×FNO/Ymax<0.5  (1)

where F represents the focal length of the entirety of the projection system, FNO represents the F number of the projection system, and Ymax represents a maximum image height in a reduction-side conjugate plane.

A polychromator system comprising: an optical element defining an aperture; a collimation mirror for receiving light via the aperture and reflecting substantially collimated light; at least a first dispersive optical component and a second dispersive optical component, each configured to disperse the substantially collimated light received from the collimation mirror by different amounts for different wavelengths and to provide cross-dispersed light having different wavelengths of light spaced along a first and second axis; and a focus mirror positioned to focus the cross-dispersed light onto a 2-D array detector to provide a plurality of aperture images of the aperture at a respective plurality of regions of the detector, each of the plurality of aperture images associated with a respective wavelength of the cross-dispersed light. Either one or both of the collimation mirror and the focus mirror is a freeform mirror having a reflective surface configured to mitigate effects of optical aberrations of the polychromator system over a plurality of the wavelengths of the cross-dispersed light along the first axis and the second axis and thereby optimise the resolution of the plurality of aperture images associated with the plurality of the wavelengths along the first axis and the second axis.

An optical lens assembly, including a first lens element, a second lens element, a third lens element, a fourth lens element, and a fifth lens element sequentially along an optical axis from a first side to a second side, is provided. The optical lens assembly satisfies the conditional expression of D34/D12≥2.600. Furthermore, other optical lens assemblies are also provided.

An imaging lens includes first, second, third, fourth, fifth and six lens elements arranged in order from an object side to an image side along an optical axis. Each of the lens element has a thickness along the optical axis. Two of thicknesses of the first to the fourth lens elements along the optical axis are the thickest and the second thickest among the abovementioned six lens elements, respectively.

A laser beam combining apparatus, and a combined stepped reflector and a filling rate calculation method thereof are disclosed. The laser beam combining apparatus includes a two-dimensional light-emitting array and the combined stepped reflector used to reflect a plurality of laser beams emitted by the two-dimensional light-emitting array. The combined stepped reflector is composed of a plurality of reflective mirrors that have the same length but sequentially increasing widths and that are stacked in succession, where the distance between centers of the laser beams reflected by the combined stepped reflector is smaller than the distance between centers of the laser beams prior to the incidence, thus increasing the filling rate of the laser beams emitted by the two-dimensional light-emitting array. A method for calculating the filling rate of the laser beam combining apparatus is also provided.

A method for illuminating samples in microscopic imaging methods, wherein a number m of different wavelengths λ.sub.i, with m>I and i=I, . . . , m, is selected for the illumination. For each of the wavelengths λ.sub.i a target phase function Δφ.sub.i(x, y, λ.sub.i) is predefined, wherein x and y denote spatial coordinates in a plane perpendicular to an optical axis z and each target phase function Δφ.sub.i(x, y, λ.sub.i) is effective only for the corresponding wavelength λ.sub.i. The target phase functions Δφ.sub.i are predefined depending on the structure of the sample and/or the beam shape and/or illumination light structure to be impressed on the light used for illumination. A total phase mask is then produced which realises all target phase functions Δφ.sub.i(x, y, λ.sub.i). This total phase mask is then illuminated simultaneously or successively with coherent light of wavelengths λ.sub.i such that the predefined structure of the illumination light is generated in the region of the sample.

A new projector design combines one spatial light modulator that affects only the phase of the illumination, and one spatial light modulator that only affects its amplitude (intensity). The phase-only modulator curves the wavefront of light and acts as a pre-modulator for a conventional amplitude modulator. This approach works with both white light and laser illumination, generating a coarse image representation efficiently, thus enabling, within a single image frame, significantly elevated highlights as well as darker black levels while reducing the overall light source power requirements.

An optimized SOI 2×2 multimode interference (MMI) coupler is designed by use of the particle swarm optimization (PSO) algorithm. Finite Difference Time Domain (FDTD) simulation shows that, within a footprint of 9.4×1.6 μm.sup.2, <0.1 dB power unbalance and <1 degree phase error are achieved across the entire C-band. The excess loss of the device is <0.2 dB.

A method, an apparatus, and a device for determining parameters of a fisheye lens are provided. The fisheye lens includes a meta-lens including a first surface and a second surface, and the first and second surfaces are each provided with a plurality of columnar structures. The method includes: obtaining a focal length and a projection mode of a fisheye lens to be designed; determining a light angle offset of each columnar structure based on the focal length and the projection mode; determining a phase distribution of the columnar structure based on the light angle offset of the columnar structure; and determining a size of the columnar structure according to the phase distribution of the columnar structure. The fisheye lens may achieve a relatively large viewing field in a short distance.