A device for measuring an aberration has an image sensor, projection optics for optically projecting onto the image sensor, an optical unit for influencing the optical projection onto the image sensor so that the result on the image sensor is a multiple image of a plurality of sub-images, wherein the optical unit has at least one region per sub-image, wherein the regions influence different lateral portions of a wavefront incident on the projection optics in different ways, and an evaluator configured to determine information relating to the aberration based on the multiple image.

The invention concerns a method for characterizing mode group properties of multimodal light traveling through an optical component, comprising: launching a reference pulse of light with a wavelength λ.sub.t from a light source into said optical component, collecting light signal output by said optical component into a Mode Group Separating optical fiber; detecting light signal output by said Mode Group Separating optical fiber. The Mode Group Separating optical fiber is a multimode fiber with an α-profile graded index core with an α-value chosen such that said fiber satisfies the following criterion at the wavelength λ.sub.t: $\frac{.Math.\mathrm{\Delta \tau }.Math..L}{\Delta T_{\mathrm{REF}}}>4$
where: Δτ is a time delay difference between consecutive mode groups; L is a length of said fiber; ΔT.sub.REF is a Full Width at Quarter Maximum of said reference pulse.

A system for a wavefront imaging sensor with high resolution (WISH) comprises a spatial light modulator (SLM), a plurality of image sensors and a processor. The system further includes the SLM and a computational post-processing algorithm for recovering an incident wavefront with a high spatial resolution and a fine phase estimation. In addition, the image sensors work both in a visible electromagnetic (EM) spectrum and outside the visible EM spectrum.

The invention concerns a method for characterizing mode group properties of multimodal light traveling through an optical component, comprising: launching a reference pulse of light with a wavelength .sub.t from a light source into said optical component, collecting light signal output by said optical component into a Mode Group Separating optical fiber; detecting light signal output by said Mode Group Separating optical fiber.

The Mode Group Separating optical fiber is a multimode fiber with an -profile graded index core with an -value chosen such that said fiber satisfies the following criterion at the wavelength .sub.t:

[00001]$\frac{.Math..Math..L}{.Math..Math.T_{\mathrm{REF}}}>4$

where: is a time delay difference between consecutive mode groups; L is a length of said fiber; T.sub.REF is a Full Width at Quarter Maximum of said reference pulse.

The invention concerns a method for characterizing mode group properties of multimodal light traveling through an optical component, comprising: providing a Mode Group Separating optical fiber in an optical path between a light source and said optical component; launching reference pulses of light with a wavelength t from said light source through said Mode Group Separating optical fiber into said optical component at discrete intervals between a core center and a core radius of said fiber.
The Mode Group Separating optical fiber is a multimode fiber with an -profile graded index core with an -value chosen such that said fiber satisfies the following criterion at the wavelength t: $\frac{.Math..Math..Math.L}{T_{\mathrm{REF}}}>4$
where: is a time delay difference between consecutive mode groups; L is a length of said fiber; T.sub.REF is a Full Width at Quarter Maximum of said reference pulses.

A device for measuring an aberration has an image sensor, projection optics for optically projecting onto the image sensor, an optical unit for influencing the optical projection onto the image sensor so that the result on the image sensor is a multiple image of a plurality of sub-images, wherein the optical unit has at least one region per sub-image, wherein the regions influence different lateral portions of a wavefront incident on the projection optics in different ways, and an evaluator configured to determine information relating to the aberration based on the multiple image.

A wavefront measurement device includes: a phase modulation unit having a spatial light modulator on which incident light is incident; a pattern generation unit configured to generate a phase pattern to be inputted to the spatial light modulator; an imaging unit having an imaging region for imaging an image of a portion of the incident light modulated by the spatial light modulator as measurement light; and an analysis unit configured to analyze a wavefront of the incident light based on an imaging result by the imaging unit, in which the pattern generation unit generates a plurality of phase patterns for which a measurement virtual pattern is shifted to positions different from each other such that a focused spot of the measurement light modulated by the spatial light modulator shifts over time to different positions in the imaging region.

The invention concerns a method for characterizing mode group properties of multimodal light traveling through an optical component, comprising: providing a Mode Group Separating optical fiber in an optical path between a light source and said optical component; launching reference pulses of light with a wavelength t from said light source through said Mode Group Separating optical fiber into said optical component at discrete intervals between a core center and a core radius of said fiber.

The Mode Group Separating optical fiber is a multimode fiber with an -profile graded index core with an -value chosen such that said fiber satisfies the following criterion at the wavelength t:

[00001]$\frac{.Math..Math..Math.L}{.Math..Math.T_{\mathrm{REF}}}>4$

where: is a time delay difference between consecutive mode groups; L is a length of said fiber; T.sub.REF is a Full Width at Quarter Maximum of said reference pulses.