CN202101661U - High-resolution guided-mode resonance angle amesdial - Google Patents

Abstract

The utility model relates to a high-resolution guided-mode resonance angle amesdial. A light source emits incident light to the surface of a guided-mode resonance wave filter, an emitting optical fiber probe is placed in an emitting light path, and reflected light emitted from the surface of the guided-mode resonance wave filter is received by a reflected light receiver and then sent to a spectrograph. Through adopting the high-resolution guided-mode resonance angle amesdial, another way is provided for precision measurement by utilizing the angle sensibility of the guided-mode resonance wave filter on the incident light to realize high-resolution angular measurement.

Description

A kind of high resolving power guide mode resonance angle dial gauge

Technical field

The utility model relates to a kind of surveying instrument, particularly a kind of high resolving power guide mode resonance angle dial gauge.

Background technology

Guide mode resonance wave filter (GMRF) structure is with its extremely narrow bandwidth; Be close to 100% reflectivity and wavelength; Advantageous characteristic such as the susceptibility of angle have obtained using widely, obtain the fabulous monochromatic light of monochromaticity, expanding communication bandwidth as in fiber optic communication field, utilizing GMRF; At biomedical aspect, utilize the GMRF structure that the susceptibility of wavelength has been made high sensitivity and do not have the label biology sensor.

The utility model content

The utility model is to the characteristics of guide mode resonance wave filter and the problem of utilization; A kind of high resolving power guide mode resonance angle dial gauge has been proposed; Utilize the guide mode resonance filter construction that the angle sensitivity of incident ray has been designed highly sensitive angle dial gauge, can survey minute angle.

The technical scheme of the utility model is: a kind of high resolving power guide mode resonance angle dial gauge; Comprise light source, guide mode resonance wave filter, launching fiber probe, reflected light receiver, spectrometer; Light source is mapped to incident light on the guide mode resonance wave filter surface through the launching fiber probe; Ejaculation reflected light in guide mode resonance wave filter surface is sent into spectrometer after receiving through the reflected light receiver.

Said guide mode resonance wave filter comprises quartz substrate and the hafnia grating above the quartz substrate.

The beneficial effect of the utility model is: the utility model high resolving power guide mode resonance angle dial gauge, utilize the guide mode resonance wave filter to realize high-resolution measurement of angle for the angle sensitivity of incident light, for precision measurement provides another approach.

Description of drawings

Fig. 1 is an incident guide mode resonance wave filter relative position synoptic diagram;

Fig. 2 is for to record the reflected light spectrogram through guide mode resonance wave filter spectrometer;

Fig. 3 is a guide mode resonance filter schematic in the utility model high resolving power guide mode resonance angle dial gauge;

Fig. 4 is the utility model high resolving power guide mode resonance angle dial gauge one-piece construction figure;

Fig. 5 is for recording the reflected light spectrogram of two-beam through guide mode resonance wave filter spectrometer.

Embodiment

The guide mode resonance wave filter is a kind of sub-wavelength grate structure, and is as shown in Figure 1, basalis, ducting layer, grating layer; Through calculating suitable grating each several part parameter, the material refractive index used, the thickness of each layer like each several part; Grating constant etc., the guide mode resonance wave filter that we let a branch of white light incide and design is surperficial, surveys catoptrical spectrum then; Can obtain the spectrogram as Fig. 2, we can know from Fig. 2, and the white light of incident has only the part of peak value place wavelength absolutely to be reflected; We claim that this wavelength is a resonant wavelength, and the reflectivity of other compositions is very little, does not almost have.When the incident angle of the white light that changes incident; The reflectance spectrum that records also can change; Mainly be that a small change can take place resonant wavelength, the minor alteration of this resonant wavelength can characterize the angle variable quantity of incident white light, and just we will record minute angle.

Utilize its susceptibility to the incident angle of incident ray, make a kind of high resolving power guide mode resonance angle dial gauge, the guide mode resonance wave filter that needs of making at first comprises following concrete steps:

A: the making of guide mode resonance grating.On quartz substrate, be coated with the thin layer that a layer thickness is the hafnium oxide material of 221nm; Cleaned quartz substrate is fixed on the coating machine top, in the hafnium oxide material that will be coated with is positioned over the crucible of coating machine bottom, closes the cavity of coating machine then; It is vacuumized; When vacuum tightness reaches 10-2Pa, just can the hafnium oxide material in the crucible be melted, hafnia becomes gaseous state and evaporates on the quartz substrate attached to the coating machine top; Through the thickness monitoring appearance, after the hafnia film layer thickness reaches 221nm on the quartz substrate, stop plated film.So just obtained being coated with the quartz substrate of hafnia film layer.

B: then on the hafnia film layer, be coated with one deck photoresist; We utilize this photoresist layer to do one deck mask; The sort of material above the film of this photoresist just as photograph usefulness, very sensitive to light, behind the exposure imaging; Sensitization partly exposure can cause the polymerization chain break, and generation can be dissolved and the unit removed.After this layer photoetching glue-line is carried out, take and go exposure below the holographic exposure system.The holographic exposure system utilizes a semi-transparent semi-reflecting level crossing; Laser beam is carried out beam splitting; Obtain the relevant laser beam of two bundles, let two bundle laser through beam expanding lens again, collimation lens intersects in one plane at last; On this plane, can produce interference fringe, this striped just shape with grating is the same.The substrate that we will coat photoresist places on this plane, makes public one minute, is placed on developer solution the inside then and develops, but when seeing substrate surface chromatic colour striped, take out substrate and use the deionized water clean substrate surfaces, residual solution and impurity on the removal substrate.Mask has just been carried out like this.

C: next will use ionic reaction etching machine the inside to carry out etching in ready-made sample; There is not the hafnia of photoresist to etch away above so just inciting somebody to action; At last the photoresist of remnants is washed off with NaOH; So just obtained the hafnia grating above the quartz substrate, structure shown in accompanying drawing 3, Here it is our the guide mode resonance wave filter that will do.

Then ready-made guide mode resonance wave filter is placed high resolving power guide mode resonance angle dial gauge as shown in Figure 4; Light source 2 through launching fiber probe 3 with incident light at an angle θ 1 incide guide mode resonance wave filter 1 surface, at this moment have a reflected light on guide mode resonance wave filter 1 surface, receive reflected light through reflected light receiver 4; Send into spectrometer 5 and obtain catoptrical spectrum; Spectrogram such as Fig. 5 have peak, i.e. a peak value among the figure; We are called resonance peak, and we record the pairing wavelength of this resonance peak is λ 1; We change the angle incident of the incident angle Δ θ of incident ray with θ 2 then; Survey its reflectance spectrum again; Obtaining another peak wavelength is λ 2, and angle variable quantity is Δ θ=θ 2-θ 1, and corresponding peak change amount is that wavelength shift is Δ λ=λ 1-λ 2; We have a fixing S value, S=Δ θ/Δ λ by the guide mode resonance wave filter of design.The guide mode resonance wave filter that each designs all has the S value corresponding with it, and just S is known.As noted earlier, when incident light changes a small angle delta θ, use spectrometer can record the drift value Δ λ of reflected light crest; Δ λ also is known; We want to know this Δ θ value, through formula: Δ θ=Δ λ * S, can be in the hope of the value of Δ θ.The limiting resolution of the spectrometer that we use is 0.06nm, is 0.004 ° through calculating the extreme angles that can survey.

Claims (2)

1. high resolving power guide mode resonance angle dial gauge; It is characterized in that; Comprise light source, guide mode resonance wave filter, launching fiber probe, reflected light receiver, spectrometer; Light source is mapped to incident light on the guide mode resonance wave filter surface through the launching fiber probe, and ejaculation reflected light in guide mode resonance wave filter surface is sent into spectrometer after receiving through the reflected light receiver.

2. according to the said high resolving power guide mode resonance of claim 1 angle dial gauge, it is characterized in that said guide mode resonance wave filter comprises quartz substrate and the hafnia grating above the quartz substrate.

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