Hyperspectral imaging apparatus

Patent metadata

Field	Value
Publication number	US-12504377-B2
Application number	US-202418600980-A
Country	US
Kind code	B2
Filing date	Mar 11, 2024
Priority date	Mar 11, 2024
Publication date	Dec 23, 2025
Grant date	Dec 23, 2025

Abstract

A compact photoluminescence hyperspectral imaging apparatus comprises a fore-optics module and a spectrometer module. The fore-optics module has a line laser for line scanning a sample. The fore-optics module comprises optical components forming an emission light signal pathway to guide a line scan emission light signal from the sample into the spectrometer module. The spectrometer module comprises a plurality of optical components forming a folded optical light signal pathway between an emission light signal entrance and a deflection mirror. The plurality of optical components including a diffraction element and the deflection mirror are arranged in a single optical plane. The deflection mirror is arranged to deflect a diffracted light signal from the diffraction element out of the optical plane into a detector positioned above or below the optical plane.

First claim

The invention claimed is:

1 . A hyperspectral imaging apparatus comprising:
a fore-optics module; and a spectrometer module; the fore-optics module having a line laser for line scanning a sample, the fore-optics module comprising optical components forming an emission light signal pathway to guide a line scan emission light signal from the sample into the spectrometer module; and the spectrometer module comprising a plurality of optical components forming a folded optical light signal pathway between an emission light signal entrance and a deflection mirror, the plurality of optical components including a diffraction element and the deflection mirror being arranged in an optical plane, the deflection mirror arranged to deflect a diffracted light signal from the diffraction element out of the optical plane into a detector positioned above or below the optical plane.

2 . The apparatus of claim 1 , wherein the plurality of optical components of the spectrometer module comprise a first mirror for collimating the emission light signal received at the emission light signal entrance and directing a collimated light signal to the light diffraction element, a second imaging mirror for directing the diffracted light signal from the diffraction element towards the deflection mirror, the first mirror, the diffraction element, the second mirror, and the deflection mirror arranged in said optical plane.

3 . The apparatus of claim 2 , wherein the plurality of optical components are arranged in a crossed Czerny-Turner configuration.

4 . The apparatus of claim 1 , wherein the diffraction element comprises a planar diffraction grating.

5 . The apparatus of claim 4 , wherein the planar diffraction grating comprises a reflective planar diffraction grating.

6 . The apparatus of claim 1 , wherein the deflection mirror is arranged to deflect the diffracted light signal perpendicularly out of the optical plane into the detector.

7 . The apparatus of claim 1 , wherein the detector is a digital camera.

8 . The apparatus of claim 7 , wherein the digital camera is a complementary metal-oxide semiconductor (CMOS) camera.

9 . The apparatus of claim 1 , wherein the entrance to the spectrometer module comprises an entrance slit having a length of equal to or longer than 2 mm.

10 . The apparatus of claim 1 , wherein the spectrometer module does not have a diffracted light signal exit slit.

11 . The apparatus of claim 1 , wherein the line laser is arranged to emit scanning line light along a scanning light signal pathway towards a sample holder of the fore-optics module, the sample holder arranged to hold or support a sample, a dichroic filter positioned in the scanning light signal pathway and arranged to allow the scanning line light to pass through it to the sample holder, the dichroic filter deflecting the line scan emission light signal reflected from the sample out of the scanning light signal pathway onto the emission light signal pathway towards the spectrometer module such that the emission light signal travels over a portion of the scanning light signal pathway prior to being deflected by the dichroic filter.

12 . The apparatus of claim 11 , wherein the dichroic filter comprises a short-pass filter.

13 . The apparatus of claim 11 , wherein the emission light signal pathway includes a long-pass filter.

14 . The apparatus of claim 11 , wherein the sample holder is motorized such that motorized movement of the sample holder enables the scanning line light of the laser to pass over the sample holder.

15 . The apparatus of claim 11 , wherein the fore-optics module includes a cylindrical lens positioned in the scanning light signal pathway to obtain an elongated light mode shape of the light emitted by the laser.

16 . The apparatus of claim 1 , wherein the laser comprises a diode laser.

17 . The apparatus of claim 16 , wherein the diode laser operates in a an ultraviolet (UV) to visible light signal range.

18 . The apparatus of claim 1 , wherein the apparatus comprises a housing containing the fore-optics module and the spectrometer module, the housing containing a black cloth to prevent or reduce ambient light reaching the detector and/or any of the optical components of the fore-optics module, and/or any of the optical components of the spectrometer module.

19 . A spectrometer module for a hyperspectral imaging apparatus, the spectrometer module comprising:
an emission light signal entrance for receiving a line laser scan emission light signal from a fore-optics module; and a plurality of optical components forming a folded optical path between the emission light signal entrance and a deflection mirror, the plurality of optical components including the deflection mirror and a diffraction element being arranged in an optical plane, the deflection mirror arranged to deflect a diffracted light signal out of the optical plane into a detector positioned above or below the optical plane.

20 . A fore-optics module for a hyperspectral imaging apparatus, the fore-optics module comprising:
a line laser arranged to emit scanning line light along a scanning light signal pathway towards a sample holder, the sample holder arranged to hold or support a sample; and a dichroic filter positioned in the scanning light signal pathway and arranged to allow the scanning line light to pass through it to the sample holder, the dichroic filter deflecting a line scan emission light signal reflected from the sample out of the scanning light signal pathway onto an emission light signal pathway towards a spectrometer module such that the emission light signal travels over a portion of the scanning light signal pathway prior to being deflected by the dichroic filter.

Assignees

• Hong Kong Applied Science & Tech Research Inst Co Ltd

Inventors

• Tse Ming Leung
• Woo Ka Ki
• Wang Naixiang
• Chan Chun Chung

Classifications

• G02B27/141

  using dichroic mirrors · CPC title

• G01N2201/06113

  Coherent sources; lasers · CPC title

• G01N2201/103

  Scanning by mechanical motion of stage · CPC title

• G01N2201/0636

  Reflectors · CPC title

• G01N2201/0634

  Diffuse illumination · CPC title