CN104516111A - System and method for coherently superposing and synthesizing multiple Airy beams to obtain high-energy bottle beams - Google Patents

Abstract

The invention discloses a method for coherently superposing and synthesizing multiple Airy beams to obtain high-energy bottle beams. A system comprises a He-Ne laser device, a collimating beam expanding lens, a reflective spatial light modulator, a control computer, a Fourier lens, a microscope objective lens and a CCD (charge coupled device) receiver which are sequentially connected with one anther. The method includes that a laser beam which is in Gaussian distribution is emitted by the laser device and is transmitted to the reflective spatial light modulator after being subjected to collimation and beam expansion, a special phase graph is loaded on the spatial light modulator and is a light intensity pattern, interference of ideal multiple Airy beams and plane beams is simulated by the computer to obtain the light intensity pattern, and the special phase graph is inputted into the spatial light modulator under the control of the computer; beams which are reflected after phases are modulated are further subjected to Fourier transformation by the aid of the Fourier lens, so that the high-energy bottle beams can be generated, can be amplified by the microscope objective lens and then are received by a CCD behind the microscope objective lens. The method has the advantage that the sizes of light bottles can be flexibly controlled.

Description

A kind of high energy light bottle beam system of many Airy beam coherence stack synthesis and method

Technical field

The invention belongs to optical technology and beam Propagation technical field, relate to a kind of method producing light bottle light beam, specifically, relate to high energy light bottle beam system and the method for a kind of many Airy beam coherence stack synthesis.

Background technology

Light bottle light beam (bottle beam) be have on the direction of propagation of light beam intensity be zero region, and in this region external space all round a kind of special hollow beam of high strength.Because it has closed dummy section in the dark and high intensity gradient, the optical characteristics of these uniquenesses and the optical characteristics of novelty, make it can be widely used in light tweezer, atom seizure, particle manipulation and Trapping of Atoms etc. just.At present, theory and experimentally existing multiple method can produce bottle beams, mainly contain and are sent out by bessel beam interferometric method, Gaussian beam interference, vortex beams method, Holographic zone plate method, combination tapered lens method etc.Wish that high energy light bottle and size can conveniently regulate for different application scenarios, and the method producing light bottle at present there is different defects.One of them defect is that optical component parameter is non-adjustable, once Optical element manufacturing completes, the light bottle beam size produced because of it also immobilizes.The needs had in these methods current in addition make complicated high precision diffraction optical element, too increase complicacy and and the cost intensive of technology.Moreover be exactly that light bottle produces the certain propagation distance of application needs, make the low impact application of the energy of light bottle.

In the last few years, Airy beam was widely used because having the features such as salt free ligands, autoacceleration, self-healing and studied.For Problems existing in the practical application of current light bottle, the present invention utilizes these peculiar optical characteristics of Airy beam, by multiple Airy beam by annular coherence stack, produce ring light bottle light beam, utilize each Airy beam salt free ligands feature, improve light bottle energy greatly by coherence stack, and by regulating the spaced apart of many Airy beam, simultaneously also realize light bottle size controlled, meet the demand that Trapping of Atoms and cell manipulate.

Summary of the invention

In order to overcome, light bottle energy in prior art is low, the defect of light bottle size not easy-regulating, the invention provides high energy light bottle beam system and the method for the synthesis of a kind of many Airy beam coherence stack, the method adopts spatial light modulator to produce the coherence stack of many Airy beam in conjunction with holographic technique, realizes high energy light bottle beam distribution.Meet the demand of atom seizure and particle manipulation.

Its technical scheme is as follows:

A high energy light bottle beam system for many Airy beam coherence stack synthesis, by He-Ne laser instrument 1, collimator and extender mirror 2, reflective spatial light modulator 3, computer for controlling 4, fourier lense 5, microcobjective 6, CCD receiver 7 is connected in sequence.

A kind of high energy light bottle beam method of many Airy beam coherence stack synthesis, comprise the following steps: first, laser instrument sends a branch of laser in Gaussian distribution, this laser is through collimation with after expanding, propagate on a reflective spatial light modulator (SLM), this spatial modulator is loaded with a specific phase figure, this phase graph is the light intensity pattern of being interfered by the many Airy beam of computer mould quasi-ideal and planar light beam and being obtained, and controls to be input in spatial light modulator by computing machine.Through this phase-modulation back reflection light beam out, then carry out Fourier transform through a fourier lense and just can produce high energy light bottle light beam, then the amplification finally by microcobjective is placed in CCD reception thereafter.

Beneficial effect of the present invention: the present invention is because of the synthesis being many Airy beam, and each Airy beam is approximate diffraction-free autoacceleration light beam, so the light bottle energy obtained improves greatly.Produce the distance between the many Airy beam in phase place additionally by computing machine regulating and controlling, can realize very neatly controlling light bottle size, meet the demand that Trapping of Atoms and cell manipulate.

Accompanying drawing explanation

Fig. 1 is the light bottle beam system schematic diagram of the generation of the embodiment of the present invention;

Fig. 2 is the phase diagram of the embodiment of the present invention;

Fig. 3 is the light bottle beam pattern of the generation of the embodiment of the present invention.

Embodiment

Below in conjunction with the drawings and specific embodiments, technical scheme of the present invention is described in more detail.

Fig. 1 is the high energy light bottle light beam schematic diagram that the present invention produces the synthesis of many Airy beam coherence stack.Comprise He-Ne laser instrument 1, collimator and extender mirror 2, reflective spatial light modulator 3, computer for controlling 4, fourier lense 5, microcobjective 6, CCD receiver 7 forms.Light bottle light beam is produced by multi beam salt free ligands autoacceleration Airy beam coherence stack, greatly improves the energy of light bottle.That many Airy beam to interference the pattern produced with planar light beam by computer for controlling 4 phase graph be input in spatial light modulator 3.Control to produce the distance between the multiple Airy beam in phase diagram by computing machine, freely realize regulation and control light bottle size flexibly.The method is combined by holographic technique and spatial light modulation technology and realized.

Particularly, the He-Ne laser instrument of laser instrument to be visible wavelength be 632.8nm; Collimator and extender mirror focal length 300mm, clear aperture 50mm; Spatial light modulator is reflective, and pixel size is 8um, and resolution is 1920*1080, service band 420-850nm; Fourier transform lens focal length 300mm; Microcobjective magnification 40 times, numerical aperture NA=0.6; CCD resolution 1920*1080.

The Gaussian laser beam launched when He-Ne laser instrument expands through collimator and extender mirror, and light beam is full of whole clear aperature; Then the directional light expanded is projected on reflective spatial light modulator, by the corresponding phase diagram of computing machine control inputs in spatial light modulator, this phase graph is the light intensity pattern of being interfered by the many Airy beam of computer mould quasi-ideal and planar light beam and being obtained, as shown in Figure 2, for 10 bundle Airy beam in this example, wherein many Airy beam can be expressed as:

$E_{10-\mathrm{airy}}(x,z)=\underset{i=1}{\overset{10}{\mathrm{\Σ}}}\mathrm{Ai}(x_i,z_i)\exp \left[i(x_i,z_i)\right]$

Wherein, Ai (x _i, z _i) exp [i (x _i, z _i)]=Ai [x _i-(z _i/ 2) ²] exp [i (x _iz _i/ 2)-i (z _i ³/ 12)]

Planar light can be expressed as:

E _plane(x，z)＝A exp(ikr)

Wherein, k is wave vector, and A is amplitude.The pattern then obtained by planar light and the 10 bundle Airy interference of light can be expressed as:

I＝[E _plane(x，z)+E _10-airy(x，z)][E ^* _plane(x，z)+E ^* _10-airy(x，z)]

Propagate in spatial light modulator by the laser beam expanded, reflected after this phase-modulation.Light after reflection modulation carries out Fourier transform through Fourier transform lens 5, forms the distribution of light bottle at the back focal plane of these lens 5.For the ease of observing, placing a microcobjective and amplifying after fourier lense 5 back focal plane, after microcobjective, then place CCD receive light bottle light beam, as shown in Figure 3, it can be expressed as:

$E_{m-\mathrm{airy}}(x,z)=\underset{i=1}{\overset{10}{\mathrm{\Σ}}}\mathrm{Ai}(x_i,z_i)\exp \left[i(x_i,z_i)\right]$

In order to meet the demand that Trapping of Atoms and cell manipulate, needing light bottle size continuously adjustabe, in fact can be produced the distance between the many Airy beam in phase place by computing machine regulating and controlling, can realize very neatly controlling light bottle size.Also by changing the quantity of multiple beam, the superposition of multiple salt free ligands Airy beam can be realized simultaneously, greatly improving light bottle energy.

The above; be only the present invention's preferably embodiment; protection scope of the present invention is not limited thereto; anyly be familiar with those skilled in the art in the technical scope that the present invention discloses, the simple change of the technical scheme that can obtain apparently or equivalence are replaced and are all fallen within the scope of protection of the present invention.

Claims (2)

1. the high energy light bottle beam system of the synthesis of Airy beam coherence stack more than a kind, it is characterized in that, by He-Ne laser instrument (1), collimator and extender mirror (2), reflective spatial light modulator (3), computer for controlling (4), fourier lense (5), microcobjective (6), CCD receiver (7) is connected in sequence.

2. the high energy light bottle beam method of the synthesis of Airy beam coherence stack more than a kind, it is characterized in that, comprise the following steps: first, laser instrument sends a branch of laser in Gaussian distribution, this laser is through collimation with after expanding, propagate on a reflective spatial light modulator SLM, this spatial modulator is loaded with a specific phase figure, this phase graph is the light intensity pattern of being interfered by the many Airy beam of computer mould quasi-ideal and planar light beam and being obtained, control to be input in spatial light modulator by computing machine, through this phase-modulation back reflection light beam out, carry out Fourier transform through a fourier lense again and just can produce high energy light bottle light beam, the CCD that then amplification finally by microcobjective is placed in thereafter receives.