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CN-121978827-A - Device using double optical wedges for optical delay line

CN121978827ACN 121978827 ACN121978827 ACN 121978827ACN-121978827-A

Abstract

The invention discloses a device using a double-optical-wedge optical delay line, which comprises a first optical wedge, a second optical wedge and a displacement table, wherein the wedge angles of the first optical wedge and the second optical wedge are alpha, the first optical wedge and the second optical wedge are arranged in parallel, an incident light beam sequentially passes through the first optical wedge and the second optical wedge, one of the first optical wedge and the second optical wedge is fixed, the other of the first optical wedge and the second optical wedge is fixed on the displacement table, and the displacement table is a one-dimensional linear displacement table, and the movement direction of the displacement table is perpendicular to the cross sections of the incident light and the optical wedges. The invention further improves the resolution of the optical path change amount in space by using the displacement table and the optical wedge, can be used for the dynamic process of femtosecond laser detection, has simple principle and arrangement, and changes the original delay line with lower cost.

Inventors

  • QIAN ZEPENG
  • ZHANG PENGJU

Assignees

  • 中国科学院物理研究所

Dates

Publication Date
20260505
Application Date
20251231

Claims (10)

  1. 1. An optical delay line device using double optical wedges is characterized by comprising a first optical wedge and a second optical wedge with wedge angles alpha and a displacement table; the first optical wedge and the second optical wedge are arranged in parallel, and an incident light beam sequentially passes through the first optical wedge and the second optical wedge; One of the first optical wedge and the second optical wedge is fixed, and the other is fixed on the displacement table; the displacement platform is a one-dimensional linear displacement platform, and the moving direction is perpendicular to the cross sections of incident light and the optical wedge.
  2. 2. The device of claim 1, wherein the non-wedge surface of the first optical wedge is an incident surface and perpendicular to the incident light, the wedge surface is an emergent surface, and the wedge surface of the second optical wedge is an incident surface and the non-wedge surface is an emergent surface.
  3. 3. The device of claim 1, wherein the first wedge is an entrance surface, the non-wedge surface is an exit surface and perpendicular to the incident light, and the second wedge is an entrance surface, the non-wedge surface is an exit surface.
  4. 4. The device of claim 1, wherein the first and second wedges are of a uniform material parameter comprising fused silica, calcium fluoride, BK7 glass.
  5. 5. The device of claim 1, wherein the front and back surfaces of the first and second wedges through which the light beams pass are coated with anti-reflection films of corresponding wavelengths.
  6. 6. The device of claim 5, wherein the thickness of the thinnest portion of the anti-reflection film is 0.5-2mm.
  7. 7. A device using a dual optical wedge optical delay line according to claim 1 wherein the wedge angle α is less than 10 °.
  8. 8. A method of obtaining an optical delay line using a double optical wedge, characterized by applying a double optical wedge optical delay line device according to any of claims 1-8, comprising the steps of: arranging said one using a dual wedge optical delay line device; starting a light source to introduce a laser beam to inject the laser beam into the first optical wedge, wherein the incident beam is perpendicular to the non-wedge surface of the first optical wedge; According to the required optical path change Setting the displacement of the displacement table 。
  9. 9. The method of obtaining an optical delay line using a dual optical wedge as claimed in claim 1, wherein when the non-wedge surface of the first optical wedge is an incident surface, the optical delay line is changed according to a required optical path length Setting the displacement of the displacement table The method specifically comprises the following steps: ; Wherein beta is the emergence angle passing through the inner part of the first optical wedge, alpha is the wedge angle of the first optical wedge or the second optical wedge, Is the refractive index of air.
  10. 10. The method of obtaining an optical delay line using a dual optical wedge as claimed in claim 1, wherein when the wedge surface of the first optical wedge is an incident surface, the optical delay line is changed according to a required optical path length Setting the displacement of the displacement table The method specifically comprises the following steps: ; wherein, beta is the emergence angle passing through the inside of the first optical wedge, and alpha is the wedge angle of the first optical wedge or the second optical wedge.

Description

Device using double optical wedges for optical delay line Technical Field The invention belongs to the technical field of optical delay lines, and particularly relates to an optical delay line device using double optical wedges. Background At the atomic and molecular level, almost all photophysical events correspond to a specific period. The vibration of atomic nuclei, the twisting of chemical bonds, often occurs between femtoseconds and picoseconds, and the separation of charges, the transfer of energy, may span between femtoseconds and nanoseconds. The delay accuracy provided by electronics is more than adequate when the time window is relaxed to nanoseconds or slower, however once the picosecond or even femtosecond scale is approximated, the electronics are limited to nanosecond thresholds except for the fringe camera which can still "photograph" with picosecond resolution. At the same time, the light excitation can promote the generation of a large number of transient species, namely excited state molecules, neutral free radicals and various ionic free radicals, and the steady state test can only give a 'time integral image' of the transient species, but dynamics details are difficult to reveal. Therefore, time-resolved techniques become key to insight into the nature of molecules. To truly realize the resolution of the magnitude of femtoseconds and above, the resolution can only be realized through a non-electrical method, the problem of time scale can be changed into a spatial problem by means of an optical delay line method, the displacement distance of a light beam on the delay line is converted into the time of displacement, and each time of accurate movement by 1 micron is equivalent to the time process of accurately resolving 3.33 femtoseconds in time, so that more dynamic processes are explored on the scale of femtoseconds and even attoseconds. But the high-resolution nanometer precision displacement table has very high use cost, is generally over two tens of thousands of RMB, and has higher use and maintenance cost, so that the experiment cost is increased greatly. Disclosure of Invention The invention aims to overcome the defects and shortcomings of the prior art and provide a delay scanning device which uses a double-optical-wedge optical delay line device and realizes higher-precision delay scanning by utilizing the combination of an optical wedge and a displacement table. In order to achieve the above purpose, the present invention adopts the following technical scheme: In one aspect, the invention provides an optical delay line device using double optical wedges, which is characterized by comprising a first optical wedge, a second optical wedge and a displacement table, wherein the wedge angles of the first optical wedge and the second optical wedge are alpha; the first optical wedge and the second optical wedge are arranged in parallel, and an incident light beam sequentially passes through the first optical wedge and the second optical wedge; One of the first optical wedge and the second optical wedge is fixed, and the other is fixed on the displacement table; the displacement platform is a one-dimensional linear displacement platform, and the moving direction is perpendicular to the cross sections of incident light and the optical wedge. The preferable technical scheme is that the non-wedge surface of the first optical wedge is taken as an incident surface and is perpendicular to incident light, the wedge surface is taken as an emergent surface, and the wedge surface of the second optical wedge is taken as an incident surface and is taken as an emergent surface. The preferable technical scheme is that the wedge surface of the first optical wedge is taken as an incident surface, the non-wedge surface is taken as an emergent surface and is vertical to incident light, and the non-wedge surface of the second optical wedge is taken as an incident surface, and the non-wedge surface is taken as an emergent surface. As a preferable technical scheme, the material parameters of the first optical wedge and the second optical wedge are consistent, and the materials comprise fused quartz, calcium fluoride and BK7 glass. As a preferable technical scheme, front and rear surfaces of the first optical wedge and the second optical wedge, through which the light beams pass, are plated with antireflection films with corresponding wavelengths. As a preferable technical scheme, the thickness of the thinnest part of the antireflection film is 0.5-2mm. As a preferred embodiment, the wedge angle α is smaller than 10 °. In another aspect, the present invention further provides a method for obtaining an optical delay line by using a dual optical wedge, which is characterized by applying the above-mentioned device using the dual optical wedge, and comprising the following steps: arranging said one using a dual wedge optical delay line device; starting a light source to introduce a laser beam to inject the laser be