CN100492505C - Liquid crystal lens element and optical head device - Google Patents

Liquid crystal lens element and optical head device Download PDF

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Publication number
CN100492505C
CN100492505C CNB2005800035419A CN200580003541A CN100492505C CN 100492505 C CN100492505 C CN 100492505C CN B2005800035419 A CNB2005800035419 A CN B2005800035419A CN 200580003541 A CN200580003541 A CN 200580003541A CN 100492505 C CN100492505 C CN 100492505C
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liquid crystal
lens element
light
crystal lens
voltage
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CN1914674A (en
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大井好晴
佐藤弘昌
清水龙一郎
野村琢治
田边让
大泽光生
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AGC Inc
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Asahi Glass Co Ltd
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Abstract

The present invention provides liquid crystal lens element comprising no movable part, having a small size, having a lens function capable of being subjected to stable spherical aberration correction including the power component corresponding to the focus variation of the incident light. The liquid crystal lens element has a variable focal length to the light transmitted through a liquid crystal(16) interposed between a pair of transparent substrates(11, 12). The variable focal length can be varied with the voltage applied to the liquid crystal(16). The liquid crystal lens comprises transparent electrodes(13, 14) provided to the respective transparent substrates(11, 12) and used to apply a voltage to the liquid crystal(16) and an irregular part(17) which has a serrated cross section and a rotational symmetry with respect to the optical axis and is formed of a transparent material on one side of the transparent electrode(13). The liquid crystal(16) is placed at least in the recesses of the irregular part(17) so as to vary the substantial index of refraction of the liquid crystal(16) depending on the applied voltage.

Description

Liquid crystal lens element and optic probe device
Technical field
The present invention relates to liquid crystal lens element and optic probe device, particularly can be and the corresponding optic probe device that optical recording media is carried out the information record and/or resets of being used for that switches to the liquid crystal lens of a plurality of different focal and this liquid crystal lens is housed according to the size that applies voltage.
Background technology
Optical recording media (being called " CD " later on), the overlayer that forms by transparent resin that has the information recording layer that forms on light incident side surface and cover this information recording layer, as this optical recording media, popularized have CD with CD and DVD with CD etc.In addition, at the optic probe device that is used for this DVD is carried out the information record and/or resets with CD, being to use wavelength as light source is the semiconductor laser of 660nm frequency band, and use NA (numerical aperture) is 0.6 to 0.65 object lens etc.
In the past, the general DVD that uses was an individual layer with the information recording layer of CD (hereinafter referred to as " single-layer optical disc "), and cover thickness is 0.6mm.But, in recent years, in order to increase the quantity of information of each sheet CD, also developed information recording layer has been formed two-layer (special use of resetting maybe can be reset and write down) CD (hereinafter referred to as " double-layer CD "), in this double-layer CD, be that the position of 0.57mm and 0.63mm forms information recording layer in the cover thickness of light incident side.
Like this, have in employing single-layer optical disc is carried out optimal design, make aberration be the optic probe device of zero object lens double-layer CD is write down and/or the situation of resetting under, if the cover thickness difference is then poor to the focusing of the incident light of information recording layer because of the corresponding generation spherical aberration of difference of cover thickness.Particularly in the double-layer CD of recordable type, the focusing difference reduces corresponding focusing power density when making record, produces the problem that causes write error.
In recent years, in order further to improve the recording density of CD, the CD that cover thickness is 0.1mm (hereinafter referred to as " BD CD ") is proposed also.In addition, to this CD carry out the recording optic probe device of information use have penetrate wavelength as the semiconductor laser of the laser of 405nm frequency band as light source, and NA be the optic probe device of 0.85 object lens.But in this case, for the double-layer CD of recordable type too, because of the corresponding generation spherical aberration of difference of cover thickness, this spherical aberration causes generation the problem of write error.
In the past, as the method for proofreading and correct the spherical aberration that the difference because of cover thickness such as double-layer CD as described above produces, known by adopting moving lens to form the method for liquid crystal lens.
(I) for example, carry out spherical aberration correction, propose the optic probe device 100 (for example, with reference to patent documentation 1) of the record reproducing that carries out CD D shown in Figure 16 in order to utilize movable lens set.
This optic probe device 100 also has the 1st and the 2nd movable lens set 160 and 170 except having light source 110, various optical system 120, photo detector 130, control circuit 140 and modulation/demodulation circuit 150.In addition, the 1st movable lens set 160 has concavees lens 161, convex lens 162 and driver 163, the convex lens that are fixed on the driver 163 162 are moved along optical axis direction, thus the magnification of finding movable lens set 160 from just (convex lens) to negative (concavees lens) continually varying varifocal from lens function.
By this movable lens set 160 of configuration in the light path of CD D, can make the incident light of the different information recording layer of the cover thickness that is incident to CD D (diagram is omitted) focus on, proofread and correct the spherical aberration that comprises the magnification component.
But, when using this movable lens set 160, need a pair of lens 161 and 162 and driver 163, therefore the problem that exists is to cause optic probe device 100 to maximize, simultaneously owing to want movable, so the mechanism design complexity.
(II) in addition, for the spherical aberration that the difference of proofreading and correct because of the cover thickness of CD produces, also proposed to adopt the optic probe device (for example, with reference to patent documentation 2) of liquid crystal lens shown in Figure 17 200.
This liquid crystal lens 200 are substrates 230 of forming transparency electrode 210 and alignment films 220 in smooth one side with the exponentiation operator sum of axisymmetric radius r, be following formula
[mathematical expression 1]
S(r)＝α 1r 2+α 2r 4+α 3r 6 …(1)
R in the formula 2=x 2+ y 2
α 1, α 2, α 3: constant
Form nematic crystal 270 transparency electrode 240 and alignment films 250, that clip by substrate 260 on the curved surface of the surface configuration S (r) that describes and constitute.
If voltage is applied between transparency electrode 210 and 240, then the molecular orientation of the liquid crystal 270 of this liquid crystal lens 200 changes, refraction index changing.Its result, poor according to the refractive index of substrate 260 and liquid crystal 270, the corrugated respective change of transmitted light.
Here, the liquid crystal 270 of the refractive index of substrate 260 when not applying voltage equates.Therefore, when this does not apply voltage, constantization of transmission corrugated of incident light.
In addition, if voltage is applied between transparency electrode 210 and 240, then produce the difference Δ n of refractive index between substrate 260 and the liquid crystal 270, transmitted light produces the distribution of the difference of the optical length that is equivalent to Δ n * S (r) (in the formula, S (r) is with reference to formula (1)).
Therefore, process,, make to proofread and correct the spherical aberration that the difference because of the cover thickness of CD D produces according to the difference Δ n that applies the corresponding adjustment refractive index of voltage by surface configuration S (r) to substrate 260, thus can aberration correction.
But, under the situation of liquid crystal lens shown in Figure 17, because liquid crystal 270 is to the maximum about 0.3 with respect to the variations in refractive index that applies voltage, therefore for the distribution Δ n * S (r) of the difference of the big optical length that produces the magnification component that is equivalent to make the incident light focal variation, must increase the concavo-convex poor of S (r).Its result, the layer thickening of liquid crystal 270 produces the driving voltage increase and responds slow problem.
Therefore, for the reducer crystal layer, more only proofread and correct the minimum spherical aberration of aberration correction quantity of removing the magnification component.But, process at surface configuration S (r) substrate 260, when only making spherical aberration corrector, produce when eccentric at the optical axis of the optical axis of the object lens that incident light focused on the optical disc information recording layer and liquid crystal lens, to produce coma, produce problem poor to the focusing of information recording layer, that can not write down or reset.
(III) owing to finding that the blackening bath crystal layer does not make the yet variable substantial lens function of magnification component that is equivalent to the incident light focal variation, liquid crystal diffraction lens 300 shown in Figure 180 (for example, with reference to patent documentation 3) have been proposed also.
This liquid crystal diffraction lens 300 are the single face formation transparency electrodes 320 at the substrate 310 of the zigzag fluctuating that forms regulation, utilize this transparency electrode 320 to clamp liquid crystal layer 340 with counter electrode 330.If voltage is applied between this electrode 320 and 330, then for unusual light polarization light, the actual refractive index of liquid crystal layer 340 is from unusual optical index n eBecome ordinary refraction index n oHere, so-called " actual refractive index " means it is the mean refractive index of thickness of liquid crystal layer direction.
In the refractive index of establishing the substrate 310 with zigzag relief fabric is n 1, when the incident light wavelength is λ, the groove depth d that zigzag rises and falls forms the relation that satisfies following formula:
d＝λ/(n e-n 1)
By when not applying voltage, accessing maximum diffraction efficiency like this, form diffraction lens from wavelength X.In addition, even the wavelength X of incident light changes, also can adjust and apply voltage, making becomes maximum diffraction with wavelength X.
In the liquid crystal diffraction lens 300 that constitute like this, owing to only require and fill out liquid crystal layer 340, make the groove that buries the zigzag fluctuating get final product, therefore compare with the such liquid crystal 270 that adopts aforementioned liquid crystal lens 200 shown in Figure 17 to proofread and correct the spherical aberration that comprises the magnification component, liquid crystal layer 340 can attenuate.
But in these liquid crystal diffraction lens 300, owing to form saturating face electrode 32 on the zigzag relief, therefore this transparency electrode 320 breaks easily in the marginal portion.In addition, if liquid crystal layer 340 attenuates, transparency electrode 320 and counter electrode 330 easy short circuits.
Patent documentation 1: the spy opens the 2003-115127 communique
Patent documentation 2: the spy opens flat 5-205282 communique
Patent documentation 3: the spy opens flat 9-189892 communique
The present invention In view of the foregoing proposes just, its purpose is to provide a kind of liquid crystal lens element, this liquid crystal lens element can realize not having the miniaturized component of moving part, be the thin liquid crystal cell of liquid crystal layer simultaneously, and have can be according to the size that applies voltage, the lens function that the spherical aberration that comprises the magnification component that is equivalent to stable incident light focal variation is proofreaied and correct.In addition, the object of the present invention is to provide a kind of optic probe device, this optic probe device is by adopting this liquid crystal lens element, can proofread and correct the spherical aberration that produces because of the difference of cover thickness in individual layer and the double-layer CD, carries out stable record and/or playback.
Summary of the invention
The present invention is made of following main points.
1. a liquid crystal lens element is pancratic liquid crystal lens element, wherein has
The a pair of transparency carrier that has transparency electrode respectively;
Between the saturating late electrode separately that this a pair of substrate has, apply the voltage bringing device of voltage;
Form and the optical axis that has for liquid crystal lens element has the serrated crosssection shape of rotational symmetry or the jagged cross sectional shape of approximate stairstepping with transparent material, simultaneously the jog that forms at least one transparency electrode in described each transparency electrode; And
At least the liquid crystal of the recessed part of the described jog of filling,
According to utilizing described voltage bringing device to be applied to the size of the voltage between described transparency electrode, make the actual refractive index respective change of described liquid crystal.
According to this structure, on the tabular surface of transparency carrier, form transparency electrode, form the jog of proofreading and correct the corrugated aberration more thereon.Its result, the good uniformity of the electric field that the liquid crystal layer that is filled with liquid crystal is applied can access stable action in the face of liquid crystal lens element.Transparency electrode has, owing to can guarantee at interval that necessarily therefore formation is difficult for producing the structure of inter-electrode short-circuit again.In addition, owing to the liquid crystal filling had serrated crosssection or with the recessed part of the transparent material of the jagged cross sectional shape of approximate stairstepping, thickness that therefore can the reducer crystal layer.Its result can realize low voltage drive and high-speed response.In addition, best aforementioned jog is for the height unanimity of each bossing and each recessed part of this transparency carrier face, promptly in the jagged cross sectional shape of jagged cross sectional shape or approximate stairstepping, recessed part promptly preferably adopts so-called Fresnel Lenses shape with respect to the degree of depth unanimity of bossing.
2. above-mentioned 1. described liquid crystal lens elements, described liquid crystal adopt has ordinary refraction index n oReach very optical index n e(n here o≠ n e), simultaneously the actual refractive index of liquid crystal layer according to the size of the described voltage that applies at no to the liquid crystal material that changes between the numerical value of the scope of ne, and the direction of orientation with the liquid crystal molecule when not applying voltage in liquid crystal layer all along the characteristic of specific direction orientation, the transparent material of described jog is for unusual light polarization light incident light refractive index n to be arranged at least simultaneously sTransparent material, refractive index n sBe positioned at n oWith n eBetween (comprise refractive index n sValue and n oAnd n eSituation about equating).
In addition, if the transparent material of described jog is ns for the unusual refractive index of light polarization light incident light, except the homogeneous refractive index transparent material, also can be birefringent material then.
According to this structure, find that liquid crystal should have different states and consistent state with the refractive index of the transparent material of jog mutually according to the size that applies voltage.By like this, can access a kind of liquid crystal lens element, it can switch the lens function of the transmission corrugated variation that makes incident light in order to proofread and correct the spherical aberration that comprises the magnification component and the indeclinable function in transmission corrugated of incident light.When particularly making the refractive index n s of described jog consistent,, do not produce the indeclinable function in transmission corrugated of the difference incident light of refractive index when finding not apply voltage because of jog and liquid crystal layer for unusual light polarization incident light with ne.In addition, when the refractive index n s that makes described jog is consistent with no,, do not produce the indeclinable function in transmission corrugated of the difference incident light of refractive index when finding not apply voltage because of jog and liquid crystal layer for the ordinary light polarized incident light.Basically do not depend on wavelength because the transmission corrugated changes, though therefore find BD with DVD with or CD the light incident liquid crystal lens element of a plurality of wavelength bands such as use and the also indeclinable function in transmission corrugated.
3. above-mentioned 2. described liquid crystal lens elements, the refractive index n of the transparent material of described jog sSatisfy the relation of following formula 2:
[mathematical expression 2]
|n e-n s|≦|n e-n o|/2
The depth d of the recessed part of described jog is gone into λ for the ripple of the light that sees through described liquid crystal simultaneously, is in the scope of following formula 3:
[mathematical expression 3]
(m-0.25)·λ/|n e-n s|≦d
≦(m+0.25)·λ/|n e-n s| …(2)
In the formula, m=1,2 or 3.
In addition, if the transparent material of described jog is n for the unusual refractive index of light polarization incident light s, except the homogeneous refractive index transparent material, also can be birefringent material then.Described liquid crystal lens element promptly is provided, and the refractive index of the transparent material of the described jog of this liquid crystal lens element satisfies the relation of following formula 4:
[mathematical expression 4]
|n e-n s|≦|n e-n o|/2
The depth d of the recessed part of described jog is in the scope of described formula (2) for described light wavelength λ simultaneously.
According to this structure, have the diameter polarized incident light of plane of polarization for the molecular orientation direction at liquid crystal, the actual refractive index n (V) of the liquid crystal layer of respective change is Δ n (V)=n (V)-n with the difference of the refractive index n s of the transparent material of jog if establish according to the size that applies voltage V s, then difference Δ n (V) d of the maximum optical length of the liquid crystal of the transparent material of bossing and recessed part changes between-m the λ at+m λ in fact according to the size that applies voltage.In addition, at Δ n (V o)=0 o'clock is promptly at the refractive index n of the transparent material of the refractive index of liquid crystal layer and jog sWhat equate applies voltage V oThe time, find the transmitted wave of incident light and indeclinable function.
In addition, also find just switching to the function of (convex lens) and negative (concavees lens) with the magnification component that applies the transmission corrugated that voltage produced before and after it.By like this, can access utilize apply voltage can switch comprise focal length, be the liquid crystal lens element of the spherical aberration of magnification component.
Under the situation of m=1, applying voltage V + 1, V -1(V + 1＜V 0＜V -1) time, Δ n (V) d=+ λ reaches-λ,
Under the situation of m=2, add the situation of m=1, applying voltage V + 2, V -2(V + 2＜V + 1＜V 0＜V -1＜V -2) time, Δ n (V) d=+2 λ and-2 λ,
Under the situation of m=3, add the situation of m=2, applying voltage V + 3, V -3(V + 3＜V + 2＜V + 1＜V 0＜V -1＜V -2＜V -3) time, Δ n (V) d=+3 λ and-3 λ,
That is, form according to value, the utilization (2m+1) of m individual apply magnitude of voltage switch comprise the transmission corrugated, be the liquid crystal lens element of the spherical aberration of magnification component.In addition, when intermediate voltage value, also finding has magnification to generate effect.
When the depth d of the recessed part of described jog satisfies formula (2), in order to find such function effectively, the best electricalresistivity of jog material FBe significantly less than the electricalresistivity of liquid crystal layer LCSpecifically, best ρ F/ ρ LCFor smaller or equal to 10 -5Its result is applied in the voltage between transparency electrode, reduces the voltage drop of jog, and voltage is applied on the liquid crystal layer effectively.
In addition, the electricalresistivity of jog material FNot the electricalresistivity who is significantly less than liquid crystal layer LCThe time, for applying voltage V between transparency electrode, the voltage drop that can produce jog is applied to the voltage V on the liquid crystal layer effectively LCTo reduce.
See as at jog material and liquid crystal layer under the situation of big resistivity of electrical insulators, apply the electric capacity C of voltage V according to jog FElectric capacity C with liquid crystal layer LCDistribute, decide the voltage V that is applied on the liquid crystal layer LCThat is, by adjusting according to serrated crosssection between transparency electrode or the electric capacity C that changes with the ratio of the thickness of the jog of the jagged cross sectional shape of approximate stairstepping and liquid crystal layer FWith C LC, can the interelectrode mean refractive index of corresponding adjustment be optical length according to the shape of jog.There is the indeclinable voltage V that applies in transmission corrugated of incident light in its result 0, or the magnification component on transmission corrugated apply voltage V for just (convex lens) + 1, or the magnification component on transmission corrugated apply voltage V for negative (concavees lens) -1By like this, can access utilize apply voltage can switch comprise focal length, be the liquid crystal lens element of the spherical aberration of magnification component.
4. each described liquid crystal lens element of above-mentioned 1. to 3. wherein, is that the phase-plate of the odd-multiple of pi/2 forms integrated with the phase differential between wavelength X and the described light.
Phase-plate and above-mentioned 1. described liquid crystal lens elements are overlapping and carry out the liquid crystal lens element of lamination 5..
According to this structure, the single liquid crystal lens element that employing can miniaturization can make polarization state also change with the corrugated one of transmitted light.
6. provide that two above-mentioned 1. described liquid crystal lens elements is overlapping and carry out the liquid crystal lens element of lamination.
According to this structure, the effect of this liquid crystal lens element is the result with the mutual addition of effect of two liquid crystal lens.Have again, when the direction of orientation of the liquid crystal molecule that constitutes liquid crystal lens element separately is orthogonal, no matter its polarization state how, all has lens effect, the cross sectional shape (contour shape) of parallel in the direction of orientation of liquid crystal molecule in addition, jog plays the effect as the different liquid crystal lens of magnification not simultaneously.
Polarizability diffraction grating and phase-plate is overlapping and carry out the liquid crystal lens element of lamination with above-mentioned 1. described liquid crystal lens elements according to this order 7..
According to this structure, the single liquid crystal lens element that employing can miniaturization can make polarization state also change with the corrugated one of transmitted light, can also produce the diffraction light that depends on polarized light.
8. optic probe device is provided, have the light source of the light that penetrates wavelength X, the photodetector that will penetrate object lens that the light optical recording media focuses on from the light of this light source, will utilize this object lens focusing and utilize the light of described optical recording media reflection to carry out the spectroscope of beam split and detect the light of described beam split, wherein
In the light path between described light source and described object lens, each described liquid crystal lens element of 1. to 4. is set.
In addition, the optic probe device that has above-mentioned any liquid crystal lens element by employing, owing to can proofread and correct the spherical aberration that comprises the magnification component that the difference because of the cover thickness in individual layer and the double-layer CD produces, also can access stable aberration than plus effect even be under the eccentric position relation, therefore realize to improve focusing, carry out the stable record and/or the optic probe device of playback information recording surface at liquid crystal lens element and object lens.
9. an optic probe device has the ejaculation wavelength X 1And wavelength X 2Here λ 1≠ λ 2) light light source, will focus on the object lens on the optical recording media from the emergent light of this light source and detect the photodetector utilize this object lens focusing and to utilize the emergent light of described optical recording media reflection, wherein, in the light path between described light source and described object lens, each described liquid crystal lens element of above-mentioned 1. to 4. is set
Simultaneously as the described wavelength X that is incident to described liquid crystal lens element 1And wavelength X 2Light, adopt the mutually perpendicular rectilinearly polarized light of plane of polarization.
10. above-mentioned 8. or 9. described optic probe devices, wherein, described optical recording media has the overlayer of coverage information layer, and the different optical recording media of this tectal thickness is write down and/or resets.
Have the optic probe device of above-mentioned any liquid crystal lens element by employing, can have wavelength X 1Incident light proofread and correct the such function of spherical aberration that the difference because of the cover thickness of CD produces according to the size that applies voltage.In addition, can have wavelength X 2Incident light irrelevant and do not make the transmission corrugated of incident light change such function with the size that applies voltage.Even its result is in wavelength X 1And wavelength X 2Light be incident under the situation of liquid crystal lens element, adopting wavelength X 2The CD of light write down and/or playback time can not produce bad influence yet.
According to the present invention, the good uniformity owing to the electric field that liquid crystal layer is applied can access stable action in the face of liquid crystal lens element, and transparency electrode can be guaranteed necessarily at interval simultaneously, and therefore formation is difficult for producing the structure of inter-electrode short-circuit.And, owing to the liquid crystal filling had zigzag or with the recessed part of the transparent material of the jagged cross sectional shape of approximate stairstepping, thickness that therefore can the reducer crystal layer, thus realize low voltage drive and high-speed response.In other words, can provide a kind of liquid crystal lens element, this liquid crystal lens element does not have moving part and can miniaturization, has simultaneously according to applying voltage and can stablize the lens function of correction to the spherical aberration that comprises magnification.
In addition, a kind of optic probe device can be provided, this optic probe device is by additional this liquid crystal lens element, can be to the spherical aberration that produces because of the difference of cover thickness in individual layer and the double-layer CD, even under the situation of liquid crystal lens element and object lens off-centre, also can carry out stable record and/or playback.
Description of drawings
Figure 1 shows that the side sectional view of the liquid crystal lens element formation of the 1st example that the present invention is relevant.
Figure 2 shows that the formation planimetric map of liquid crystal lens element shown in Figure 1.
Figure 3 shows that the curve map of the difference of the optical length that utilizes the transmission corrugated that liquid crystal lens generates, α is made as transverse axis radius r, is the curve that the difference of optical length is represented in the unit with the wavelength X, β be from α deduct the integral multiple of wavelength X, as the curve of the difference of the optical length below the zero above λ, γ is expression with respect to the difference of optical length is the curve that zero face and β form the difference of symmetrical optical length.
Figure 4 shows that the side view that liquid crystal lens element of the present invention is switched the effect when applying voltage, convergence transmission corrugated when (A) expression applies voltage V+1, (B) the transmission corrugated is dispersed when (C) expression applies voltage V-1 in the transmission corrugated that do not have corrugated change of expression when applying voltage Vo.
Fig. 5 is the amplification view between transparency electrode in the side view of liquid crystal lens element of the present invention.
Figure 6 shows that side sectional view with the liquid crystal lens element formation of incorporate the present invention's the 2nd example of phase-plate.
Figure 7 shows that the orthogonal side sectional view that like that liquid crystal lens element of the present invention's the 3rd example of liquid crystal lens element lamination is constituted of the direction of orientation of liquid crystal molecule.
Figure 8 shows that the side sectional view that the liquid crystal lens element of the present invention's the 4th example of the liquid crystal lens element lamination that the transmission corrugated of switching is different constitutes.
Figure 9 shows that side sectional view with the liquid crystal lens element formation of phase-plate and polarizability diffraction grating and incorporate the present invention's the 5th example of diffraction light.
Figure 10 shows that light source with in photodetector is contained in single component and the side view of the optical unit configuration example that the incorporate the present invention of liquid crystal lens element is relevant.
Figure 11 shows that the pie graph of the optic probe device of the 6th example that the relevant liquid crystal lens element of the present invention's the 2nd example is housed.
Figure 12 shows that the pie graph of the optic probe device variation of the 6th example that the relevant liquid crystal lens element of the present invention's the 2nd example is housed.
Figure 13 shows that the optic probe device pie graph that is equipped with the 7th example of the incorporate optical unit of liquid crystal lens element of the present invention's the 5th example.
Figure 14 shows that liquid crystal lens element of the present invention utilizes voltage to carry out the curve of the mensuration example of focus switching.
Figure 15 shows that the calculated value curve that uses the corrugated aberration that optic probe device that liquid crystal lens element of the present invention is housed produces the different DVD CD of cover thickness.
Figure 16 shows that in the past the optic probe device pie graph of movable lens set as the spherical aberration correction element is housed.
Figure 17 shows that the side sectional view of liquid crystal lens configuration example in the past.
Figure 18 shows that the side view of liquid crystal diffraction lens configuration example in the past.
Label declaration
1A, 1B, 61 semiconductor lasers (light source)
The 1C double-wavelength light source
2A, 2B, 2C, 53 diffraction grating
The diffraction grating of 2C wavelength selectivity
3 dichroic prisms
4 spectroscopes
The holographic spectroscope of 4B
5 collimation lenses
6 object lens
7 cylindrical lenses
8,8A, 8B, 62 photodetectors
10,10A, 10B, 10C, 20,30,40,50 liquid crystal lens elements
11,12,12A, 12B, 21 transparency carriers
13,13A, 13B, 14,14A, 14B transparency electrode
15,15A, 15B sealing
16,16A, 16B, 16C liquid crystal
17,17A, 17B, 17C jog
18,18A, 18B AC power
22 phase-plates
51 birefringent diffraction gratings
52 layer of adhesive material
60 optical units
63 derbies
64 assemblies
70,80,90 optic probe devices
The D CD
Embodiment
Below, with reference to description of drawings example of the present invention.
[the 1st example]
Below, with reference to cut-open view shown in Figure 1 and planimetric map shown in Figure 2, describe the configuration example of the relevant liquid crystal lens element 10 of the present invention's the 1st example in detail.
The liquid crystal lens element 10 that this example is relevant has transparency carrier 11 and 12, transparency electrode 13 and 14, sealing 15, liquid crystal (liquid crystal layer) 16, jog 17 and AC power 18.
Wherein, jog 17 usefulness transparent materials form, and for example use refractive index n in this example sThe homogeneous refractive index transparent material form, the cross section has zigzag or with stepped jagged in fact shape, the optical axis (Z axle) with respect to incident light in the zone of effective diameter φ has rotational symmetry.Here, the recessed part that preferably adopts jog is consistent Fresnel Lenses shape with respect to the degree of depth of its bossing.
Below, an example of the manufacturing step of this liquid crystal lens element 10 is described.
At first, a tabular surface at transparency carrier 11 forms transparency electrode 13.On a tabular surface (surface till among Fig. 1) of this transparency electrode 13, use refractive index n again sThe homogeneous refractive index transparent material, form the cross section and be zigzag or with the jog 17 of stepped jagged in fact shape.
Then, form transparency electrode 14, on transparency carrier 12, the binding material beyond the diagram of sneaking into gap control material is printed, make figure, thereby form sealing 15, and overlapping with aforesaid transparency carrier 11, carry out crimping, make dummy cell.Has ordinary refraction index n from being arranged on the inlet (not shown) of a sealing part of 15, injecting oReach very optical index n e(n here o≠ n e) liquid crystal 16, seal this inlet, liquid crystal 16 is sealed in the unit, as the liquid crystal lens element 10 of this example.
Like this, at the filling of the recessed part at least liquid crystal 16 of jog 17, use 18 pairs of transparency electrodes 13 of AC power and 14 to add the alternating voltage of square wave, the molecular orientation by such liquid crystal 16 changes, and the actual refractive index of liquid crystal (layer) 16 is from n eBecome n oIts result, according to the size that applies voltage, liquid crystal 16 changes with the difference Δ n (V) of the refractive index of jog 17, and transmitted light changes for the corrugated of incident light.
Here, by the jog 17 that the homogeneous refractive index transparent material forms, can be organic materials such as ultraviolet curable resin, thermal effect resin and photoresist, also can be SiO 2Or Al 2O 3Or SiOxNy inorganic material such as (here, xy represent the element ratio of O and N).That is the refractive index n of homogeneous refractive index transparent material, s, so long as have the n of comprising oOr n eN oWith n eThe transparent material of middle refractive index value get final product.
Jog 17 is after the surface of transparency electrode 13 forms the homogeneous refractive index transparent material layer of regulation thickness, it is concavo-convex to utilize photoetching or reactive ion etching to be processed into, and also can utilize metal die that homogeneous refractive index transparent material layer transfer printing jog is formed.
In addition, for for applying the variation that voltage obtains the difference Δ n (V) of big refractive index, the liquid crystal molecular orientation direction of liquid crystal 16 that preferably is filled in recessed part is consistent with the polarization surface direction that is incident to liquid crystal lens element 10.For example, in Fig. 2 that the direction of orientation of liquid crystal molecule (that is, very the direction of optical index ne) is consistent with X-direction, make the rectilinearly polarized light incident of plane of polarization with X-direction.
For the direction of orientation that makes liquid crystal molecule is consistent with X-direction,, solidifies the back and carry out friction treatment along X-direction and get final product as long as at the oriented materials (not shown) such as surface coated polyimide of transparency electrode 14 and jog 17.Also can adopt the material of polyimide, friction treatment is carried out on its surface as jog 17.Except the friction treatment of polyimide, also can adopt oblique vapor-deposited film of SiO or light poly-to film etc., make the orientation unanimity of liquid crystal molecule.
In addition, in order to apply voltage by the 141 pairs of transparency electrodes 14 of electrode that form in transparency carrier 11 1 sides, sneak into the conductive metal particle to sealing 15 in advance, seal crimping, thereby find to have electric conductivity in the seal thickness direction, with transparency electrode 14 and electrode 11 conductings.Electrode 131 that is connected with electrode 13 and the electrode that is connected with transparency electrode 14 141 are connected AC power 18, thereby can add voltage liquid crystal 12.
Then, in following explanation zigzag or with the cross sectional shape of stepped jagged in fact jog 17.In order to use liquid crystal lens 10 of the present invention, generate to proofread and correct the transmission corrugated of the spherical aberration that the difference because of the cover thickness of CD produces, generate the transmission corrugated of the magnification component of giving plus or minus simultaneously, in the transmission corrugated of the plane wave that is incident to liquid crystal lens 10, for optical axis center (true origin: light x=y=0), make and to describe the difference OPD of optical length of light of the position by leaving radius r with the power series of following formula:
[mathematical expression 5]
OPD(r)＝a 1r 2+a 2r 4+a 3r 6+a 4r 8+ …(3)
In the formula, r 2=x 2+ y 2
α 1, α 2...: constant (with reference to [table 1] described later)
Here, in Fig. 3, represent transverse axis is made as radius r, is the object lesson of the curve of unit representation with lambda1-wavelength λ with the difference OPD of optical length with label α.
Under the situation of the incident light of the relevant wavelength X of phase place unanimity, the transmission corrugated of difference of optical length with integral multiple of λ can regard same as.Therefore, the curve of representing with α of Fig. 3 (optical length poor) is cut apart with the interval of wavelength X, and expression is that the curve β of difference of the optical length of zero face projection is same with curve α in fact to the difference of optical length.All in λ, the cross section becomes zigzag to the difference of the optical length shown in the curve β.
Here, be during at the specific insulation ρ F/ ρ LC of the transparent material of jog 17 smaller or equal to 10-5, the voltage that is applied between transparency electrode 13 and 14 is applied on the liquid crystal 16 effectively.
Below, illustrate between such transparency electrode apply voltage and liquid crystal 16 apply under the condition (it being made as " Case1 ") that voltage equates in fact the effect of the cross sectional shape of jog 17 and liquid crystal lens element 10.
When transparency electrode 13 and 14 is added voltage V, if establishing liquid crystal (layer) 16 is n (V) with respect to the unusual actual refractive index of the light of light polarization light, then the difference of the refractive index of jog 17 that is made of the homogeneous refractive index transparent material and liquid crystal 16 is Δ n (V)=n (V)-n s
For example, applying voltage V + 1Down, poor for the optical length on the transmission corrugated that generates the curve β that is equivalent to Fig. 3 is to satisfy the relation of following formula as long as the depth d of jog shown in Figure 1 11 is set
[mathematical expression 6]
d＝λ/Δn(V +1) …(4)
In the formula, λ: incident light wavelength
Δ n (V + 1): apply voltage V + 1In the difference formula of (jog 17 and liquid crystal 16) refractive index of F, establish and satisfy Δ n (V + 1) 0 apply voltage V + 1
Here, apply change in voltage, thereby the difference Δ n of refractive index is changed by making.For example:
I applies under the voltage V0 constantization of transmission corrugated of liquid crystal lens element 10 what become Δ (V0)=0.
In addition, ii) become Δ n (V-1)=-the applying under the voltage V-1 of Δ n (V+1), the transmission corrugated that produces the difference of the optical length shown in the curve r of Fig. 3.This difference that is equivalent to for optical length is zero face and the transmission corrugated of the curve β of Fig. 3 in the face of the difference of the optical length of title.
But, owing to form the refractive index n of the homogeneous refractive index transparent material of jog 17 sBe to be in to comprise refractive index value n 0Or n 2N 0With n eBetween (comprise refractive index n sValue and n 0And n sSituation about equating) therefore value exists magnitude of voltage V 0And V + 1Or V -1So the refractive index at liquid crystal 16 is n (V + 1) and n (V -1) time, the jog 17 that is formed by the homogeneous refractive index transparent material is processed into zigzag or with stepped jagged in fact cross sectional shape, makes the space distribution of the difference that becomes the optical length of the curve β that is equivalent to Fig. 3 and curve γ.
In the liquid crystal lens element 10 of this example, if make the refractive index n of the homogeneous refractive index transparent material that forms jog 17 sSatisfy the relation of following formula:
[mathematical expression 7]
|n e-n s|≦|n e-n o|/2
Then certainly exist the magnitude of voltage V that forms following formula + 1＜V 0＜V -1, promptly
Δn(V 0)＝0
Δn(V +1)＝-Δn(V -1)>0
Therefore, for AC power 18, apply voltage V by switching + 1, V 0, V -1, can switch three kinds of transmission corrugateds selectively.In addition, if the scope of following formula:
[mathematical expression 8]
|n s-[(n o+n e)/2]|≦(n e-n o)/4
Then we can say the refractive index n of homogeneous refractive index transparent material sEqual (n in fact o+ n e)/2.
In addition, the refractive index that does not apply ground of liquid crystal 16 is n e, applying V + 1And V -1The time, poor for the optical length that generates the curve β that is equivalent to Fig. 3 and curve γ preferably is made as the depth d of jog 17 scope of following formula:
[mathematical expression 9]
0.75·[λ/|n e-n s|]≦d
≦1.25·[λ/|n e-n s|]
This is equivalent to the situation of the m=1 in the formula (2).
Here, applying voltage V + 1, V 0, V -1(V here, + 1＜V 0＜V -1) under, the plane wave that is incident to liquid crystal lens 10 forms the transmission corrugated shown in Fig. 4 (A), (B), (C) respectively and penetrates.That is,, can access and positive amplification ratio, no magnification, the corresponding lens function of negative magnification according to the voltage that applies of transparency electrode 13 and 14.
In addition, at magnitude of voltage V + 1With V 0Centre or magnitude of voltage V 0With V -1The applying under the voltage V of centre, main according to and the corresponding ratio of this magnitude of voltage V, produces two kinds of transmission corrugateds (Fig. 4 (A) and (B) shown in corrugated or the corrugated of Fig. 4 (B) shown in reaching (C)).
More than, illustrated in this example under the condition of Case 1, generation is the form of the liquid crystal lens element (being equivalent to m=1 in formula (2)) of β with the difference OPD of the optical length that the difference OPD of the optical length of representing with α of Fig. 3 is cut apart at interval with wavelength X, but also can be the form that is equivalent to the liquid crystal lens element of m=2 or 3 in formula (2).In this case, become the pairing transmission of the difference OPD corrugated of the optical length that the α of Fig. 3 is cut apart at interval with wavelength m λ (m=2 or 3) here.
Specific insulation ρ at the transparent material of jog 17 FNot the anti-ρ of specific insulation that is significantly less than liquid crystal 16 LCThe time, according to the relative dielectric constant ε of the transparent material that depends on jog 17 FAnd thickness d FElectric capacity C F, and depend on the relative dielectric constant ε of liquid crystal 16 LCAnd thickness d LCElectric capacity C LC, give jog 17 and liquid crystal (layer) 16 with the voltage distribution that is applied between transparency electrode 13 and 14.
That is, adopting resistance R for jog 17 and liquid crystal (layer) 16 respectively F, R LCAnd electric capacity C F, C LCEquivalent electrical circuit in, can apply voltage V for the interchange of the a-c cycle f between transparency electrode, that calculates liquid crystal (layer) 16 applies voltage V LC
In addition, the specific insulation ρ that below illustrates at jog 17 and liquid crystal 16 FAnd ρ LCEnough big, in equivalent electrical circuit according to the electric capacity C of jog 17 and liquid crystal (layer) 16 FAnd C LCDecide voltage distribution to be, i.e. fx R to jog 17 and liquid crystal (layer) 16 F* C FAnd f * R LC* C LCThan 1 under the enough little condition (it being made as " Case2 "), about the effect of the cross sectional shape and the liquid crystal lens element 10 of jog 17.
Figure 5 shows that among Fig. 1 of sectional view of expression liquid crystal lens element 10 enlarged drawing with jog between transparency electrode 13 and 14 17 and liquid crystal 16 amplifications.In this Fig. 5, that establishes transparency electrode 13 and 14 is spaced apart certain value G.In addition, the thickness d of jog 17 FAccording to distributing the bed thickness d of liquid crystal 16 to d from zero LCAccording to from G to G-d, distributing.Here, d F+ d LC(=G) is certain value.
In Case2, apply voltage V for exchanging between the transparency electrode 13 and 14, that distributes to liquid crystal (layer) 16 applies voltage V LCRatio V LC/ V represents with following formula:
[mathematical expression 10]
V LC/V＝C F/(C F+C LC)
＝L/(L+(ε LC/ε F)×(d F/d LC)} …(5)
In the formula, ε LC: the relative dielectric constant of liquid crystal 16
ε F: the relative dielectric constant of jog 17
Here, because the thickness d of jog 17 FWith the zigzag that forms Fresnel Lenses or corresponding according to distributing to d from zero with the jagged cross sectional shape of approximate stairstepping, so d F/ d LCAccording to distributing to d/ (G-d) from zero.Its result, liquid crystal (layer) 16 apply voltage V LCWith the shape of jog 17 should produce space distribution.
For liquid crystal (layer) 16 is applied voltage effectively, preferably adopt the material of the big jog 17 of relative dielectric constant ε F, make the ratio V of formula (5) LC/ V increases.Because the relative dielectric constant ε of liquid crystal (layer) 16 LCMore than or equal to 4, therefore preferably adopt relative dielectric constant ε for approximately more than or equal to 4 F
In addition, because general liquid crystal has the anisotropy dielectric constant, the relative dielectric constant ε of long axis of liquid crystal molecule direction 11Relative dielectric constant ε with the liquid crystal molecule short-axis direction LDifference, therefore along with applying voltage, the orientation of liquid crystal molecule changes, since the change in orientation of liquid crystal molecule, the relative dielectric constant ε of liquid crystal (layer) 16 LCAlso change.Therefore, in formula (5), reflection relative dielectric constant ε LCCorresponding to V LCVariation, that determines liquid crystal (layer) 16 applies voltage V LCSpace distribution corresponding to the shape of jog 17.Because V LCCorresponding to d FChange, therefore be expressed as V after this LC[d F].In addition, V LC(0) equals to apply between electrode voltage V.
The situation of Case2 is different with Case1, owing to the voltage V that liquid crystal (layer) 16 is applied LCShape corresponding to jog 17 is different, so liquid crystal (layer) 16 is for the unusual actual refractive index n (V of the incident light of light polarization light LC[d F]) will produce space distribution.In Fig. 5, the thickness d of jog 17 FIt is n that the transparent electricity of position has the optical length between 13 and 14 s* d F+ n cV LC[d F]) * d LC, with respect to the Fresnel Lenses center (d that does not have jog 17 FThe difference OPD of the optical length of optical length n (V) * G=0) forms following formula:
[mathematical expression 11]
OPD＝{n s×d F+n(V LC[d F])×(G-d F)}
-n(V)×G …(6)
Thickness dF is according to distributing to d from zero, and the difference OPD of optical length is according to distributing from zero OPDd to following worker:
[mathematical expression 12]
OPD d＝{n s×d+n(V LC[d])×(G-d)}-n(V)×G
＝{n(V LC[d])-n(V)}×G
-{n(V LC[d])-n s}×d
For example, applying voltage V + 1Down, poor for the optical length on the transmission corrugated that generates the curve β that is equivalent to Fig. 3 is as long as make the difference OPD of optical length dBe λ (i.e. 0.75 λ～1.25 λ) in fact, decide the thickness d of jog 17 and the interval G of transparency electrode 13 and 14, be both the thickness that adopts jog 17 and get final product from zero cross sectional shape to d.
Here, apply voltage V by change, the difference OPD of the optical length of formula (6) will change.For example,
I) at the thickness d of jog 17 FAccording to from zero when d distributes, exist the difference OPD of the optical length of formula (6) to apply voltage V with respect to what the wavelength X of incident light became enough little value 0At this moment, constantization of transmission corrugated of liquid crystal lens element 10.Here, the difference OPD of enough little optical length is smaller or equal to λ/5 specifically, is preferably less than to equal λ/10.
In addition, ii) at the difference OPD of optical length dFor in fact-V of voltage in fact of λ (promptly from-0.75 λ to-1/25 λ) under, can generate the transmission corrugated of the difference of the optical length shown in the curve γ of Fig. 3.This difference that is equivalent to for optical length is zero face and the curve β of Fig. 3 is the transmission corrugated in the face of the difference of the optical length of title.
Therefore, for AC power 18, apply voltage V by switching + 1, V 0, V -1, can switch three kinds of transmission corrugateds selectively.
Here, applying voltage V + 1, V 0, V -1Following, the plane wave that is incident to liquid crystal lens 10 forms the transmission corrugated shown in Fig. 4 (A), (B), (C) respectively and penetrates.That is,, can access and positive amplification ratio, no magnification, the corresponding lens function of negative magnification according to the voltage that applies of transparency electrode 13 and 14.Identical with the situation of Case1 condition, except the difference OPD that generates the optical length that the difference OPD of the optical length of representing with α of Fig. 3 is cut apart at interval with wavelength X is the liquid crystal lens element of curve β, also can be the difference OPD that is equivalent to optical length dBe the form of the liquid crystal lens element of m λ (m=2 or 3) in fact.In this case, form the pairing transmission of the difference OPD corrugated of the optical length that the curve α of Fig. 3 is cut apart at interval with wavelength m λ (m=2 or 3 here).
In addition, different with the situation of Case1, when generating three kinds of transmission corrugateds, the refractive index n of the homogeneous refractive index transparent material of jog 17 sAlso can equal the ordinary refraction index n of liquid crystal 16 in fact oOr unusual optical index n e
For example, at n s=n 0, make anisotropy specific inductive capacity (Δ ε=ε //-ε ⊥) is positive liquid crystal when evenly being orientated,, makes (V when not applying voltage if form jog 17 + 1The difference OPD of optical length=0) d=-(n e-n o) * d becomes λ, and then under any situation of Case1 to Case2, very the light polarization light plane wave that is incident to liquid crystal lens 10 all forms the transmission corrugated that is equivalent to positive amplification ratio shown in Fig. 4 (A) and penetrates.If increase transparency electrode 13 and 14 s' the voltage that applies, then under the situation of Case1, apply voltage with height more than or equal to 10V, the refractive index of liquid crystal (layer) 16 approaches n s, can access the transmission corrugated that is equivalent to the no magnification shown in Fig. 4 (B), but not produce the transmission corrugated that is equivalent to the negative magnification shown in Fig. 4 (C).But, under the situation of Case2,, can generate the transmission corrugated that is equivalent to the no magnification shown in Fig. 4 (B) and be equivalent to the transmission corrugated of the negative magnification shown in Fig. 4 (C) with the voltage that applies smaller or equal to 5V.
Promptly, Case2 compares with Case1, by selecting refractive index and relative dielectric constant, the thickness d of jog 17 and the interval G of transparency electrode 13 and 14 etc. of liquid crystal 16 and jog 17, because therefore the design freedom height of the photoelectricity characteristic of liquid crystal lens element 10 can generate low voltage drive or diversified transmission corrugated.In addition, Case2 compares with Case1, because thickness d that can attenuate jog 17, therefore can shorten the manufacture process of film forming and concavo-convex processing.
In addition, preferably make the refractive index n of jog 17 sEqual the ordinary refraction index n0 of liquid crystal (layer) 16 in fact, the advantage that has in this case is, because the value that does not apply voltage V between pipe electrode how, for the ordinary light polarized light, jog 17 does not produce the poor of refractive index with liquid crystal (layer) 16, therefore be incident to constantization of transmission corrugated of ordinary the polarized light of liquid crystal lens element 10, can access high-transmission rate.That is, be incident to liquid crystal lens element 10 and want to make particular beam not produce the corrugated to change when carrying out transmission at a plurality of light beams, as long as be incident to liquid crystal lens element 10 as the ordinary light polarized light.For example, the different wave length incident that DVD uses and CD uses, owing to only find the magnification switching effect of liquid crystal lens element 10 with wavelength, therefore as long as be incident to liquid crystal lens element 10 as unusual light polarization light and be used as the ordinary light polarized light for CD and be incident to liquid crystal lens element 10 for DVD for DVD.
In addition, in this example, it is situation for the liquid crystal lens element 10 of the difference OPD that generates the axisymmetric optical length of describing with formula (3), its component structure and operating principle have been described, but the liquid crystal lens element of the difference OPD of production (3) optical length that is equivalent to asymmetrical coma of axis calibration or astigmatism etc. in addition, also can utilize the concaveconvex shape of homogeneous refractive index transparent material to process and recessed part filling liquid crystal is made according to same principle.
In addition, in this example, be to make the absolute value of the difference OPD utilize the optical length that liquid crystal lens element 10 generates for such smaller or equal to lambda1-wavelength λ, set the depth d of jog 17, making cross sectional shape is zigzag, but when not needing high-speed response, also can process jog 17, make the absolute value of difference OPD of optical length become more than or equal to lambda1-wavelength λ.
In this case, compare,, therefore be applied to the good uniformity of the electric field on the liquid crystal, the inner evenness height of driving voltage and response speed because electrode gap is certain with the patent documentation 2 described liquid crystal lens on [background technology] hurdle.Equally, different with the patent documentation 3 described liquid crystal diffraction lens on [background technology] hurdle, the difference of optical length with apply the big or small corresponding of voltage and change continuously.
In addition, at the absolute value of the difference OPD of the optical length that will proofread and correct for smaller or equal to lambda1-wavelength λ the time, do not need to make the section shape of the jog 17 that constitutes by the homogeneous refractive index transparent material of liquid crystal lens element 10 to form zigzag, the difference of optical length with apply the big or small corresponding of voltage and change continuously.
In addition, in this example, shown is to adopt the liquid crystal 16 with positive anisotropy specific inductive capacity, the liquid crystal molecule of this liquid crystal 16 is not when applying voltage and substrate 11 and 12 surperficial parallel-oriented, and according to the size that applies voltage, liquid crystal molecule is arranged along the vertical direction on the surface of substrate 11 and 12, but also can be other liquid crystal aligning or liquid crystal material.For example, also can be with liquid crystal with negative anisotropy specific inductive capacity, the liquid crystal molecule of this liquid crystal is orientated perpendicular to substrate surface when not applying voltage, and according to applying voltage V, liquid crystal molecule is arranged along the parallel direction of substrate surface.
In addition, in this example, be that to adopt refractive index be n for the material that will form jog 17 sThe homogeneous refractive index transparent material, but also can adopt molecular orientation direction in real estate along the birefringent materials such as high molecule liquid crystal of folk prescription to unanimity.In this case, the very optical index of preferably establishing birefringent material is n s, make ordinary refraction index equal the ordinary refraction index no of liquid crystal, make the molecular orientation direction (the very direction of optical index) of birefringent material consistent simultaneously with the direction of orientation of liquid crystal molecule.By adopting such structure, because for ordinary light polarized light incident light, no matter the size that applies voltage how, liquid crystal is consistent with the ordinary refraction index of birefringent material, so constantization of transmitted light corrugated.
In addition, in this example, shown structure is to be that transparency electrode 13 and transparency electrode 14 apply alternating voltage by whole electrodes that each one surface that spreads all over transparency carrier 11 and 12 is provided with respectively to liquid crystal 16.But among the present invention, in addition, also can adopt at least one electrode of transparency electrode 13 and transparency electrode 14 for example spatially to be cut apart, and can independently apply the structure of different alternating voltages.By like this, can generate the space distribution of the difference OPD of more various optical length.
In addition, also can be with the transparency electrode of this space segmentation as resistive film with desirable resistance, make to apply voltage and distribute along radial direction, make the added voltage of liquid crystal along the radial direction tilt distribution.
[the 2nd example]
Below, with reference to Fig. 6 the liquid crystal lens element 20 that the present invention's the 2nd example is relevant is described.In addition, in the present embodiment, for the part identical with the 1st example, additional same label, and avoid repeat specification.
The liquid crystal lens element 20 of this example is in the relevant liquid crystal lens element 10 of aforesaid the 1st example, again additive phase plate 22 and transparency carrier 21 and constitute.That is, in this liquid crystal lens element 20, transparency carrier 12 with the opposite one side of transparency electrode 14 installed surfaces, and transparency carrier 21 between, clip the phase-plate 22 that forms by birefringent material, and form integrated.
As phase-plate 22, be to adopt organic membrane such as polycarbonate to be extended and to have the birefringent film of slow axis along bearing of trend, utilize binding material to be bonded between transparency carrier 12 and 21.In addition, also can adopt the high molecule liquid crystal film, it is to the 21 coating of liquid crystalline monomers of the transparency carrier after the orientation process, form the regulation thickness after, carry out polymerizing curable and form.Perhaps, also can adopt birefringece crystal such as crystal, replace transparency carrier 21 as phase-plate 22, fixing with transparency carrier 12 bondings.
No matter under which kind of situation, the optical axis direction of phase-plate 22 is an X-axis with respect to the direction of incident light polarization face, the direction of shape angle at 45 in the XY plane.For example, go into the incident light of λ with respect to ripple, the lagged value that makes phase-plate 22 is 1/4 odd-multiple of wavelength X, and promptly phase differential is the odd-multiple of pi/2, becomes circularly polarized light by the light that sees through liquid crystal lens element 20 like this and penetrates.
Therefore, by optic probe device being installed and used the liquid crystal lens element 20 of this example, can the corrugated of transmitted light and polarized light state be changed enough single elements.
[the 3rd example]
Below, with reference to Fig. 7 the relevant liquid crystal lens element 30 of the present invention's the 3rd example 3 is described.In addition, in this example, for the part identical with the 1st example, additional same label, and avoid repeat specification.
The liquid crystal lens element 30 of this example is a liquid crystal lens element 10 that the 1st example is relevant, overlapping up and down under the such relative to each other state of two jogs 17, the structure that adopts such lamination (still, transparency carrier 11 is public), as structure roughly, have the 1st liquid crystal lens element 10A, the 2nd lens element 10B and they are applied the AC power 18 of alternating voltage.
Promptly, among the 1st liquid crystal lens element 10A of this liquid crystal lens element 30, have two transparency carriers 11 and 12A, at the transparency electrode 13A that forms on these transparency carriers and 14A, the jog 17A that on transparency electrode 14A, forms and be sealed in transparency electrode 13A and liquid crystal 16A in the space between the transparency electrode 14A of jog 17A is set.In addition, the 2nd liquid crystal lens element 10B also constitutes equally with the 1st liquid crystal lens element 10A, but public transparency carrier.
Below, the manufacture method of this example is described
At first, form transparency electrode 14A and 14B respectively on the surface of each transparency carrier 12A and 12B.Then, on the tabular surface of these transparency electrodes 14A and 14B, adopting refractive index respectively is n sThe homogeneous refractive index transparent material, form the cross section and be zigzag or with the jog 17A and the 17B of stepped jagged in fact shape.Each one side of these jogs 17A and 17B is processed into the same concaveconvex shape that optical axis (Z axle) with respect to incident light has rotational symmetry.In addition, form transparency electrode 13A and 13B on the two sides of transparency carrier 11.
Then, on each transparency carrier 12A and 12B, form the binding material that will sneak into the interval control material is made figure by printing sealing 15A and 15B respectively.Then, each transparency carrier 12A and 12B and transparency carrier 11 is overlapping, make jog 17A consistent with the rotation axes of symmetry of jog 17B, carry out crimping again, make dummy cell.Then, inject liquid crystal, seal this inlet simultaneously, liquid crystal 16A and 16B are sealed in the unit, make liquid crystal lens element 30 from the inlet (not shown) of the part that is arranged on sealing.In addition, make transparency electrode 13A and 13B conducting,, make transparency electrode 14A and 14B conducting simultaneously, as common electrode as common electrode.
In the liquid crystal lens element 10A that forms like this, utilize AC power 18 between common electrode, to add the alternating voltage of square wave.So the molecular orientation of liquid crystal 16A and 16B applies with this that voltage is corresponding to change, the actual refractive index of liquid crystal layer is from n eBecome n oIts result, the difference Δ m of the refractive index of liquid crystal 16A and 16B and jog 17A and 17B changes, and transmitted light changes for the corrugated of incident light.
Though the 1st and the 2nd liquid crystal lens element 10A shown in Figure 7 and the formation of 10B and effect are identical with liquid crystal lens 10 shown in Figure 1, the liquid crystal molecular orientation direction of liquid crystal 16A and 16B is orthogonal, and this point is different.That is, in the 1st and the 2nd liquid crystal lens element 10A and 10B, the orientation process direction at liquid crystal layer interface is orthogonal.Its result according to this example, no matter the polarization of incident light light state how, according to applying voltage, for example can correspondingly obtain having the lens function of positive amplification ratio such shown in Fig. 4 (A), (B), (C), no magnification, negative magnification.
In addition, becoming Δ n (V 0)=0 apply voltage V 0Down, when the incident light that is equivalent to unusual light polarization light is arranged for liquid crystal layer, the transmission corrugated of the 1st and the 2nd liquid crystal lens spare 10A and 10B does not change, but when the incident light that is equivalent to the ordinary light polarized light being arranged for liquid crystal layer, no matter the size that applies voltage how, the transmission corrugated of the 1st and the 2nd liquid crystal lens element 10A and 10B produces the difference n with refractive index o-n sCorresponding certain variant.
Therefore the 1st and the 2nd liquid crystal lens element 10A and 10B change no matter the incident polarization light state how, all produces this certain transmission corrugated because the direction of orientation of its liquid crystal 16A and 16B is orthogonal.In order to offset such voltage V that applies oUnder certain transmission corrugated change, the surface that is preferably in transparency carrier 10A or 12B forms rectifying plane.
Perhaps, adopt, form jog 17A and 17B, by applying voltage V like this at the equal birefraction materials such as high molecule liquid crystal of the ordinary light birefraction of identical with the direction of orientation of liquid crystal 16A and 16B respectively direction of orientation oCan make constantization of transmission corrugated of liquid crystal lens element 30 down.
[the 4th example]
Below, with reference to Fig. 6 the liquid crystal lens element 40 that the present invention's the 4th example is relevant is described.In addition, in this example, for the identical part of the 1st and the 2nd example, additional same label, and avoid repeat specification.
The liquid crystal lens element 40 of this example is compared with liquid crystal lens element 30 shown in Figure 7, and the structure of the 1st and the 2nd liquid crystal lens element 10A and 10C is with following aspect difference.
The liquid crystal aligning direction of the 2nd liquid crystal lens element 10C is different with the 2nd liquid crystal lens element 10B of the 3rd example, is the identical direction of orientation of liquid crystal 16A with the 1st liquid crystal lens element 10A.In addition, the contour shape of the jog 17C of the 2nd liquid crystal lens 10C is different with jog 17A, and the difference OPD of the optical length shown in the curve α of Fig. 3 that usefulness formula (3) is described is different mutually.Have again, utilize AC power 18A and 18C respectively independently, liquid crystal 16A and 16C are added the alternating voltage of square wave.
By like this, have very light polarization light time with the corresponding plane of polarization of direction of orientation of liquid crystal 16A and 16C in incident, the 1st and the 2nd liquid crystal lens element 10A and 10C play as the independent effect that produces the different liquid crystal lens of magnification respectively.
For example, applying voltage V + 1And V 0And V -1Be PA if establish the magnification of the 1st liquid crystal lens element 10A down, + 1, PA 0(+0), PA -1, the magnification of establishing the 2nd liquid crystal lens element 10C simultaneously is PC + 1, PC 0(=0), PC -1, and the magnitude relationship of establishing them is PA + 1＜PC + 1＜0＜PC -1＜PA -1
At this moment, apply voltage by utilizing AC power 18A and 18C not to adjust, liquid crystal lens element 40 can generate 7 kinds of (PA + 1＜PC + 1)＜PA + 1＜PC + 10＜PC -1＜PA -1＜(PA + 1＜PC + 1) different magnifications.
Its result by optic probe device being installed and used the liquid crystal lens element 40 of this example, can proofread and correct the amount of spherical aberration that comprises 7 kinds of magnification components that the difference because of cover thickness generates.
[the 5th example]
Below, with reference to Fig. 9 the liquid crystal lens element 50 that the present invention's the 5th example is relevant is described.In addition, in this example, for the identical part of the 1st and the 2nd example, additional same label, and avoid repeat specification.
The liquid crystal lens element 50 of this example is in the liquid crystal lens 10 shown in the 1st or the 2nd example, at the single face (one side of transparency electrode is not set) of transparency carrier 12 and be installed between the phase-plate 22 of one side of transparency carrier 21, clip birefringent diffraction grating 51 and bonding material layer 52.
Birefringent diffraction grating 51 is that the single face (one side of transparency electrode is not set) at transparency carrier 12 forms the birefringent material layer that is made of high molecule liquid crystal, and it is processed into the cross sectional shape of concavo-convex grating, thus form dielectric grid diffraction grating 51.Adopt the binding material of being made by the homogeneous refractive index transparent material again, it fills out the recessed part at least of birefringent diffraction grating 51, as bonding material layer 52, simultaneously with the transparency carrier bonding that is formed with phase-plate 22.
The birefringence grating 51 that is formed by high molecule liquid crystal carries out orientation process, makes the molecule of liquid crystal 16 and high molecule liquid crystal mutually to orthogonal.That is, on transparency carrier 12, form the alignment films (not shown) of carrying out orientation process along Y direction, and the coating of liquid crystalline monomer, carry out polymerizing curable, by the high molecule liquid crystal of such formation along Y direction orientation (the very direction of optical index) unanimity.Utilize with carving and reactive ion etching, forming the cross section is the birefringent diffraction grating 51 of concaveconvex shape again.
Recessed part to birefringent diffraction light 51, the filling refractive index equals the cementing agent of the ordinary refraction index of high molecule liquid crystal in fact, form bonding material layer 52, by the ordinary light polarized light transmission in such formation incident light, the unusual polarizing diffraction grating of light polarization optical diffraction.
The cross sectional shape of birefringent diffraction grating 51 can be a rectangular shape shown in Figure 9, in order to obtain high diffraction efficiency for specific diffraction number of poles, also can adopt zigzag fashion.The concavo-convex degree of depth (D) of the very optical index of birefringent diffraction grating 51 high molecule liquid crystal by suitably setting the form dielectric grid diffraction grating and poor (the Δ N) of the refractive index of the refractive index of bonding material layer 52 and this high molecule liquid crystal long-pending is (Δ N * D), can obtain the diffraction efficiency of desirable diffraction progression for the incident light of the very light polarization light of wavelength X.In addition, in the grating face, forms the hologram of the distribution of stipulating, can spatially control the diffraction direction of incident light by the angle that constitutes grating space and grating length direction.
Phase-plate 22 be with the 2nd example (with reference to Fig. 6) in the identical phase-plate of phase place anti-22 of explanation, if the optical axis direction of phase-plate 22 is the direction of X-axis shape angle at 45 in the XY plane for the direction that needs with respect to incident light polarization, establish its lagged value in order to penetrate 1/4 of light wavelength lambda.
Have again, in the liquid crystal lens element 50 of this example, as shown in Figure 9, form diffraction grating 53, produce 0 order diffraction light (straight ahead transmitted light) and ± 1 order diffraction light with respect to incident light on the surface of transparency carrier 11.Diffraction grating 53 is used as the tracking three light beams of CD in optic probe device for example.
Below, the effect of this example is described.
If from transparency carrier 11 1 sides, rectilinearly polarized light with plane of polarization of X-direction is incident to the liquid crystal lens element 50 of this example, then according to utilizing AC power 18 to be applied to the size of the voltage on the liquid crystal lens element 10, transmission corrugated respective change is incident to the polarizability diffraction grating that is made of birefringence grating 51 and bonding material layer 52 as the ordinary light polarized light.And the light that does not utilize this polarizability diffraction grating to carry out the transmission of diffraction utilizes phase-plate 22 to become circularly polarized light, sees through liquid crystal lens element 50.
In addition, if with the light of outer reflectings surface such as the CD reflection of diagram once more from the transparency carrier 21 1 side incidents of liquid crystal lens element 50, then utilize phase-plate 22 to become the rectilinearly polarized light of plane of polarization with Y direction, be incident to the polarizability diffraction grating as unusual light polarization light, therefore produce diffraction, penetrate from liquid crystal lens element 50.
Like this, integrated by liquid crystal lens element 10 is formed polarizability diffraction grating 51, phase-plate 22, diffraction grating 53, with in the device respectively one by one the situation of installation elements compare because positional precision improves, therefore can access stable performance.
Below, illustrate that such liquid crystal lens element 50 forms one with semiconductor laser and photodetector in same assembly and the unit block (hereinafter referred to as " optical unit 60 ") formed with reference to Figure 10.
Semiconductor laser body 60 and photodetector 62 that this optical unit 60 has ejaculation rectilinearly polarized light plane of polarization, wavelength X of X-direction are fixed on the derby 63, put into assembly 64.In the photodetector 62 integrated converting optical signals is electric signal after, to this signal carry out signal amplify with and the circuit used of signal Processing.Light outgoing and light incident side at this assembly 64 are provided with opening portion, have fixed liquid crystal lens element 50 in this opening portion bonding, form one, constitute the structure of blocking.
If such optical unit 60 is installed in optic probe device, then become have the function of produce following the tracks of simultaneously with the diffraction grating of three light beams, and apply the function of the corresponding aberration correction of voltage and in straight ahead transmission on the outlet and on the loop efficiently towards the polarized light of photodetector beam split entirely from the liquid crystal lens element of spectroscopical function, make the optic probe device miniaturization.
[the 6th example]
Below, DVD and the CD record of CD and the optic probe device 70 of playback usefulness of the relevant liquid crystal lens element 20 of the present invention's the 2nd example is equipped with in explanation with reference to Figure 11.In addition, in this example, for the part identical with the 2nd example, additional same label, and avoid repeat specification.
The optic probe device 70 of this example has light source i.e. the 1st and the 2nd semiconductor laser 1A and 1B, the 1st and the 2nd diffraction grating 2A and 2B, dichroic prism 3, spectroscope 4, collimation lens 5, object lens 6, cylindrical lens 7, photodetector 8, in addition, on the light path between spectroscope 4 and the collimation lens 5, has liquid crystal lens element 20.
Below, the effect of this example is described.
(i) the DVD situation of CD:
Penetrate, in the paper of Figure 11, have simultaneously the wavelength X of plane of polarization from DVD with semiconductor laser 1A 1The emergent light of (=660nm) utilizes diffraction grating 2A to produce the three light beams of following the tracks of usefulness.Then, see through dichroic prism 3,, be incident to liquid crystal lens element 20 with spectroscope 4 reflections.The light that sees through this liquid crystal lens element 20 becomes circularly polarized light, utilizes collimation lens 5 to form directional light, utilizes object lens 6 to focus on the information recording layer of DVD with CD D.
In addition, object lens 6 driver (not shown) that utilizes focus servo and tracking servo to use can move.Light with the reflection of the reflecting surface of CD D sees through object lens 6 and collimation lens 5 once more, sees through liquid crystal lens element 20 again, becomes the rectilinearly polarized light with plane of polarization vertical with paper, a part of light transmission spectroscope 4.Then, see through the focus servo that utilizes method of astigmatism and use and the cylindrical lens 7 of setting, focus on photodetector 8.In addition, though utilize the light of spectroscope 4 reflections to focus on the luminous point of semiconductor laser 1A through original light path, but owing to be that plane of polarization sends the vertical rectilinearly polarized light of light with laser instrument, therefore laser instrument is sent not influence, make laser instrument send intensity stabilization.
(ii) CD is with the situation of CD:
In addition, from the wavelength X of CD with semiconductor laser 1B plane of polarization that penetrate, that have vertical paper 2The emergent light of (=790nm) utilizes diffraction grating 2B produce to follow the tracks of the three light beams of usefulness, in dichroic prism 3 reflections, makes consistent the advancing of light of the wavelength X 1 that optical axis and DVD use, and reflects with spectroscope 4.Then, the wavelength X used of this catoptron and DVD 1Light identical, utilize collimation lens 5 and object lens 6, focus on the information recording layer of CD with CD D.In addition, the wavelength X of using with light path after the reflecting surface reflection of CD and DVD 1Light path identical.
In the optic probe device 70 of this example, adopt when sending the big semiconductor laser of output power at semiconductor laser 1A and 1B, to send polarization surface vertical for return polarization surface and the laser instrument that make return laser light device luminous point, preferably makes the phase-plate 22 (with reference to Fig. 6) in the liquid crystal lens element 20 go into λ for ripple 1And wavelength X 2Become 1/4 wavelength plate.
Specifically, be for wavelength X 1With wavelength X 2Middle wavelength, respectively lagged value is carried out lamination at the high molecule liquid crystal layer of 1/4 wavelength and 1/2 wavelength, making its optical axis angle is desirable angle.
Then, use the optic probe device 70 that liquid crystal lens element 20 of the present invention (with reference to Fig. 6) is housed, illustrate below for cover thickness different individual layer and DVD-dual layer record and the record reproducing of using CD of resetting and move.
(i) situation of single-layer optical disc (cover thickness 0.60mm):
Because design object lens 6, make that the aberration for the single-layer optical disc D of cover thickness 0.60mm be minimum, so write down and/or playback time at single-layer optical disc D, between the electrode of liquid crystal lens element 20, add alternating voltage V 0This is, because liquid crystal 16 is consistent with the refractive index of jog 17, therefore shown in Fig. 4 (B), the transmission corrugated is constant.
The (ii) situation of double-layer CD (cover thickness 0.57mm):
Write down and/or playback time at information recording layer, between electrode, add alternating voltage V the cover thickness 0.57mm in the double-layer CD + 1, make the transmission corrugated of liquid crystal lens element 20 become the spherical wave that focuses on a little.
At this moment, because the refractive index of liquid crystal 16 greater than jog 17, therefore shown in Fig. 4 (A), becomes the transmission corrugated that positive amplification ratio promptly is equivalent to convex lens.That is, utilize object lens 6, can focus on the information recording layer of cover thickness 0.57mm effectively.
The (iii) situation of single-layer optical disc (cover thickness 0.63mm):
In addition, the information recording layer outside the diagram of cover thickness 0.63mm is being write down and/or playback time, between electrode, adding alternating voltage V -1, make the transmission corrugated of liquid crystal lens element 20 become the spherical wave of dispersing a little.At this moment, because the refractive index of liquid crystal 16 less than jog 17, therefore shown in Fig. 4 (C), becomes the transmission corrugated that negative magnification promptly is equivalent to concavees lens.That is, utilize object lens 6, can focus on the information recording layer of cover thickness 0.63mm effectively.
Therefore, switch to V by the voltage that applies with liquid crystal lens element 20 0, V + 1, V -1Thereby, with single-layer optical disc and double-layer CD, realize stable record reproducing for the different DVD of cover thickness.
Like this, the optic probe device 70 relevant according to this example, liquid crystal lens element 20 are not only proofreaied and correct the spherical aberration that the difference because of the cover thickness of CD D produces, and can also add to be equivalent to the magnification that the focal position changes and to divide volume switching function.Therefore, for example settle in addition with object lens 6 and use, the radial direction along CD D when object lens 6 are followed the tracks of moves, and eccentric with liquid crystal lens element 20 generations, even in this case, aberration does not almost worsen yet.Its result compares with the liquid crystal cell of spherical aberration corrector only, can realize stable record and/or playback.
In addition, in liquid crystal lens element 20, be equivalent to the shape of the m=2 or 3 the jog 17 of formula (2) by employing, owing to can switch 5 kinds or 7 kinds of transmission corrugateds respectively, therefore for the different CD of cover thickness, can carry out more accurate aberration correction.
In addition, if adopt the liquid crystal lens element 30 of the 3rd example shown in Figure 7, replace liquid crystal lens element 20, then owing to not only corrective action is arranged for the polarized light in outlet, vertical polarized light for the loop also has corrective action, therefore also improves the focusing to photodetector.
In addition,, replace liquid crystal lens element 20, then not only can proofread and correct the aberration of the different CD of three kinds of cover thicknesss, can also proofread and correct the aberration of cover thickness in addition if adopt the liquid crystal lens element 40 of the 4th example shown in Figure 8.Therefore, even the optical system of discrepant CD of cover thickness or whole optic probe device is remaining when spherical aberration is arranged, also can carry out more accurate pixel correction.
In addition, in liquid crystal lens 20, because the rectilinearly polarized light vertical with plane of polarization in outlet as the liquid crystal incident of ordinary light polarized light to liquid crystal lens element 20, therefore produces the difference n with refractive index o-n sCertain transmission corrugated shown in corresponding changes.For it is offset, as long as form correcting element to the recessed part filling homogeneous refractive index compaction material of the rectifying plane of the concaveconvex shape that is equivalent to liquid crystal 16.Here, adjust the refractive index of birefringent material and compaction material, make that the ordinary light polarized light for liquid crystal produces the poor of optical length, do not produce the poor of optical length for unusual light polarization light.
At this moment, because the wavelength X that CD uses 2Polarized light become the ordinary light polarized light, to the liquid crystal incident of liquid crystal lens element 20, therefore no matter liquid crystal lens element 20 how apply voltage, the transmission corrugated does not change.
That is, aberration is worsened, and CD is carried out stable record reproducing with CD.
Here, the synoptic diagram of optic probe device 80 for example shown in Figure 12 is such, adopts to separate configuration DVD about 100 μ m during with the double-wavelength light source 1C of the luminous point of semiconductor laser, can constitute simple structure with semiconductor laser and CD in single component.
This optic probe device 80, the diffraction grating 2C that adopts wavelength selectivity replaces diffraction grating 2A and 2B among Figure 11 as the three light beams generating device of following the tracks of usefulness.
The diffraction grating 2C of this wavelength selectivity is the wavelength X that DVD is used 1Light produce diffraction and transmission and wavelength X that CD is used 2Light produce the diffraction grating of diffraction or the wavelength X that CD is used 2Light produce diffraction and transmission and wavelength X that DVD is used 1Light produce the diffraction grating of diffraction, perhaps with the element of their laminations, can suppress to produce unwanted scattered light, obtain high light utilization ratio.
In addition, this optic probe device 80 is by disposing liquid crystal lens element 20 in the light path between double-wavelength light source 1C and spectroscope 4, can try hard to the implement device miniaturization.In addition, integrated by making liquid crystal lens element 20 with the diffraction grating 2C of wavelength selectivity, further make equipment miniaturization.
In addition, in this example, be to use the optic probe device 80 of the liquid crystal lens element 20 that wavelength moves as individual layer light source, that DVD is used and double-layer CD D as the semiconductor laser of 660nm frequency band to be illustrated, but use the optic probe device of the liquid crystal lens element that wavelength moves as individual layer light source, that BD is used and double-layer CD D as the semiconductor laser of 405nm frequency band also can access same effect and effect for being equipped with for being equipped with.
[the 7th example]
Below, the optic probe device 90 of the present invention's the 7th example is described with reference to Figure 13.In addition, in this example, for the part identical with the 6th example, additional same label, and avoid repeat specification.
The optic probe device 90 of this example has DVD unit 90A, CD unit 90B, dichroic prism 3, collimation lens 5, object lens 6.
DVD is the optical unit shown in Figure 10 60 that illustrates in the 5th example with unit 90A, and promptly DVD constitutes the unit with semiconductor laser 1A (61), photodetector 8A (62) and liquid crystal lens element 50 and the outer fixing one that forms of assembly bonding of diagram.In addition, the CD unit is with CD semiconductor laser 1B, photodetector 8B and holographic spectroscope 4B and assembly formation one.
Below, the effect of this example is described
(i) about record and/or the playback of DVD with CD:
Write down with CD and/or reset about this DVD, be to use unit 90A that DVD uses, the optical unit 60 shown in promptly.
DVD from optical unit 60 penetrates, has the wavelength X of plane of polarization with semiconductor laser 1A in the paper of Figure 13 1The emergent light of (=66nm) sees through liquid crystal lens element 50, becomes the three light beams of circularly polarized light, sees through dichroic prism 3.Then, this transmitted light utilizes collimation lens 5 to form directional light, utilizes object lens focusing at the information recording layer of DVD with CD D.
In addition, with reverse the advancing of light of the reflecting surface of this CD D reflection, see through object lens 6 and collimation lens 5 and dichroic prism 3 once more, 1/4 wavelength plate that sees through in the liquid crystal lens element 50 is phase-plate 22 (with reference to Fig. 9) again.Then, this transmitted light becomes the rectilinearly polarized light with plane of polarization vertical with the paper of Figure 13, utilizing in the liquid crystal lens element 50 is that the polarizability diffraction grating (with reference to Fig. 9) that birefringent diffraction grating 51 and bonding material layer 52 constitute carries out diffraction by holographic spectroscope, focuses on the sensitive surface of photodetector 8A effectively.
(ii) about the record reproducing of CD with CD:
In addition, CD is to use the CD unit 90B with semiconductor laser 1B and photodetector 8B and holographic spectroscope 4B formation integral component with CD with the record reproducing of CD.
Wavelength X from semiconductor laser 1B ejaculation 2The light transmission of (=790nm) will produce the incorporate holographic spectroscope 4B of diffraction grating that follows the tracks of with three light beams.
Then, this transmitted light advances after with dichroic prism 3 reflection, makes the wavelength X that optical axis and DVD use 1The light unanimity, and utilize collimation lens 5 and object lens 6 to focus on the information recording layer of CD with CD D.
In addition,, see through object lens 6 and collimation lens 5 once more,, utilize holographic spectroscope 4B that a part of light is carried out diffraction again, focus on the sensitive surface of photodetector 8B with dichroic prism 3 reflections with reverse the advancing of light of the reflecting surface of CD D reflection.
Like this, in this example, the DVD different for cover thickness is identical with the 6th example with the action that individual layer and double-layer CD D carry out stable record and/or playback usefulness.Therefore,, can simplify the assembling adjustment of optic probe device 90, make whole equipment miniaturization simultaneously according to the optic probe device 10 of this example, and weight reduction.
Embodiment
[example 1]
Below, the specific embodiment of the liquid crystal lens element of the present invention 20 shown in the 2nd example is described with reference to Fig. 6.
The manufacture method of this liquid crystal lens element 20 at first, is described.
On the glass substrate of transparency carrier 11, form nesa coating (ITO film), with it as transparency electrode 13.The coating refractive index is n on this transparency electrode 13 again sThe homogeneous refractive index material of (=1.66) is a photosensitive polyimide, makes it form thickness d (=5.5 μ mm).
Then, adopt the such ultraviolet transmittance of the shape of the curve β be equivalent to Fig. 3,, develop behind the sintering ladder mask pattern the photosensitive polyimide irradiation ultraviolet radiation along the ladder mask that radial direction distributes.Its result (is processed to form cross sectional shape and is jog as shown in Figure 6 17 jagged, have rotational symmetry for the optical axis (Z axle) of incident light at effective diameter φ in=4.9mm) the zone.Again friction orientation being carried out along X-direction in the surface of the jog 17 that formed by polyimide handles.Transparent material as the jog 17 that is formed by polyimide that obtains like this adopts its specific insulation ρ FSpecific insulation ρ than liquid crystal 16 LCLow low-resistance material more than 106 or 106.
In addition, form nesa coating (ITO film) as the glass substrate of the transparency carrier 12 of transparency electrode 14 on behind the polyimide film of the about 50nm of coating film thickness, carry out sintering, the friction orientation processing is carried out along X-direction in the polyimide film surface.To sneak into the binding material of the interval control material of diameter 7 μ m more thereon and make figure, form sealing 15, it is overlapped with transparency carrier 11, carry out crimping, make the dummy cell that transparency electrode is spaced apart 7 μ m by printing.
Then, from inlet (not shown) the injection liquid crystal 16 of dummy cell, seal this inlet, as liquid crystal lens element shown in Figure 6 10.
This liquid crystal 16 adopts has ordinary refraction index n o(=1.50) reach very optical index n eThe nematic crystal of the positive anisotropy specific inductive capacity of (=1.78).In addition, with the plane parallel of the orientation of liquid crystal molecule and transparency electrode 13 and 14 and along the recessed part of the consistent liquid crystal 16 filling jogs 17 of X-direction.In addition, the inclined-plane of jagged jog 17 is owing to the inclination that is maximum about 3 °, so the orientation of liquid crystal molecule can be regarded as parallel with the transparency electrode face.
Then, behind the polyimide film of the about 50nm of coating film thickness on the glass substrate of transparency carrier 21, carry out sintering, the direction that edge, polyimide film surface and X-axis shape folder at 45 is right is carried out friction orientation and is handled.
Coating of liquid crystalline monomer thereon, make it become thickness 6.6 μ m, carry out polymerizing curable then, make by slow axis along, ordinary refraction index consistent with the right direction of X-axis shape folder at 45 and very the difference of optical index be 0.2 the film formed phase-plate 22 of high molecule liquid crystal.Then, with binding material that phase-plate 22 is fixing with transparency carrier 12 bondings, transparency carrier 21 grades and liquid crystal lens element 10 are bonding, as liquid crystal lens element 20.
The lagged value of this phase-plate 22 (Rd) is
R d＝0.20×6.6
＝1.32μm
(=666nm) 5/4 times has the function of 114 wavelength plates to be equivalent to the wavelength X that DVD uses.
Transparency electrode 13 and 14 to the liquid crystal lens element 20 that obtains like this connects AC power 18, and the condition by the Case1 shown in very little the 1st example of the voltage drop that is equivalent to jog 17 like this is applied to voltage on the liquid crystal 16 effectively.If make to apply voltage and increase from 0V, then liquid crystal (layer) 16 along the actual refractive index of X-direction from n e(=1.78) become n o(=1.50).Its result, for the rectilinearly polarized light incident light of plane of polarization with X-axis, poor (the Δ n) of liquid crystal 16 and the refractive index of relief members 17 from
Δn max(＝n e-n s)＝0.12
(in the formula, n s=1.66)
Become
Δn min(＝n o-n s)＝-0.16
According to the thickness distribution of the liquid crystal 16 of filling in the recessed part of jog 17, transmission corrugated respective change.
Here, for example for use wavelength X (=660nm), the DVD single-layer optical disc of cover thickness 0.60mm, having designed the object lens of numerical aperture (NA) 0.65 and focal length 3.05mm, made that aberration is zero, is that 0.57mm reaches if such object lens are used for cover thickness.The DVD double-layer CD of 063mm, the difference of then maximum optical length is about 0.15 λ, and generation is equivalent to square mean corrugated aberration and is about 43m λ, the spherical aberration of [rms].
Therefore, proofread and correct this spherical aberration, process jog 17, make that the transmission corrugated when not applying voltage is equivalent to the coefficient value a shown in following [table 1] in order to use liquid crystal lens element 20 1～a 5The difference OPD of optical length of formula (3) expression.Here, the difference OPD of the optical length of formula (3) is a unit with [μ m], and r is a unit with [mm].
[table 1]
Coefficient Value
a 1 -0.744431
a 2 0.004292
a 3 0.004880
a 4 0.001341
a 5 0.000112
By like this, use the coefficient value a of [table 1] 1～a 5, generate the transmission corrugated of the difference of the optical length that curve β that the integral multiple that deducts wavelength X from the difference of the optical length of the curve α that is equivalent to Fig. 3 of formula (3) expression obtains (be equivalent to more than or equal to zero, smaller or equal to the optical length of λ poor), Fig. 3 represents.
Here, since poor (the Δ n) of the liquid crystal when not applying voltage 16 and the refractive index of jog 17 as previously mentioned, be
Δn(＝n e-n s)＝0.12
Therefore for the liquid crystal 16 that utilizes filling in jog 17 and this protruding lower part generates above-mentioned transmission corrugated, as long as satisfy aforesaid formula (4).That is, in formula (2), during m=1,
Δn×d＝0.66μm
According to this formula, the depth d (μ m) of decision jog 17 makes the difference of maximum optical length be equivalent to wavelength X=660nm (=0.66 μ m).
By like this, the degree of depth of jog 17 (d) is made as d=5.5 μ m, is processed into cross sectional shape shown in Figure 1.Also can utilize the jagged jog 17 of approximate stairstepping in addition.In order to generate the smooth transmission corrugated of the curve α that is equivalent to Fig. 3, preferably the degree of depth (d) with jog 17 is made as
(0.75×λ/Δn)≤d≤(1.25×λ/Δn)
In addition, because the effective diameter of jog 17 is 4.9mm, so maximum radius is 2.45mm.
The DVD that is incident to liquid crystal lens element 20 is with wavelength X (=660nm) transmission corrugated (V when not applying voltage + 1=0), become the focused light shown in Fig. 4 (A), expression is equivalent to focal length (f) and is the convex lens effect of f=675mm.Then, apply voltage if increase, then at V 0During=2.5V the left and right sides, become Δ n (V 0Look like shown in Fig. 4 (B))=0, transmitted wave, keeps carrying out transmission with incident corrugated same wave face constant like that (no magnification).Apply voltage if increase again, then at V =1During=6V the left and right sides, become Δ n (V -1Δ n (the V of)=- + 1), the transmission corrugated becomes the diverging light shown in Fig. 4 (C), and expression is equivalent to focal length (f) and is the concavees lens effect of f=-675mm.
[example 2]
Below, the specific embodiment when explanation is contained in the liquid crystal lens element 20 of aforementioned [example 1] on the optic probe device 70 of the 6th example shown in Figure 11.In addition, therefore the formation of this optic probe device 70 is omitted here owing to be illustrated in the 6th example.
When the single-layer optical disc D that uses at the DVD with cover thickness 0.60mm carries out record reproducing, be V if establish the voltage that applies of liquid crystal lens element 20 0About=2.5V, then incident light utilizes object lens 6 to focus on information recording layer.
For the double-layer CD D that DVD uses, be V if establish the voltage that applies of liquid crystal lens element 20 + 1About (=0V), then incident light focuses on the information recording layer of cover thickness 0.57mm, if the facility making alive be V-1 (=6V) about, then incident light focuses on the information recording layer of cover thickness 0.63mm.I am what situation of opinion, and the calculated value of remaining square mean corrugated aberration all becomes smaller or equal to 3m λ [rms].
In addition, be that 0.555mm is in the scope of 0.585mm, if apply voltage and be made as V in cover thickness + 1, perhaps cover thickness be 0.585mm in the scope of 0.615mm, if apply voltage and be made as V0, perhaps have again to be in cover thickness.615mm is V if apply voltage in the scope of 0.645mm -1, then the calculated value by so remaining respectively square mean corrugated aberration all is reduced to approximately smaller or equal to 20m λ [rms].
In addition, in order to follow the tracks of, object lens 6 along the radial direction that partly coils D move ± during the 0.3mm left and right sides, though produce eccentricly with liquid crystal lens element 20, because corresponding generation aberration therewith not, so focus point does not degenerate yet.
Therefore, by liquid crystal lens element 20 voltage that is applied to is switched to V 0, V + 1, V -1Thereby, realize that individual layer and double-layer CD D that DVD is used carry out the stable record and the optic probe device of playback respectively.
[example 3]
Then, use its specific insulation ρ for the transparent material as jog 17 in the liquid crystal lens element of the present invention 20 shown in the embodiment of example 1 FSpecific insulation ρ more than or equal to liquid crystal 16 LCMaterial the time embodiment, describe following with reference to Fig. 6.
The manufacture method of the jog 17 in this liquid crystal lens element 20 at first, is described.
On the transparency electrode 13 of film forming on the glass substrate of transparency carrier 11, utilize the ordinary refraction index n of sputtering method formation and liquid crystal 16 oThe refractive index n of Xiang Denging in fact sHomogeneous refractive index material SiOxNy (here, x and y represent the element ratio of O and the N) film of (=1.507).Here, using the discharge gas of sneaking into oxygen and nitrogen in Si sputtering target and the Ar gas, is n by such formation refractive index sSiOxNy film transparent homogeneous refractive index, thickness d (=2.94 μ m).The relative dielectric constant ε of SiOxNy FBe 4.0, specific insulation ρ FFor more than or equal to 10 10Ω cm.
Further again, by adopting the photoetching of photomask, resist is formed figure after, utilize reactive ion etching method processing SiOxNy film, make it be equivalent to the shape of the curve γ of Fig. 3.Its result (in=4.9mm) the zone, with the sawtooth cross sectional shape of 8 grades of stepped Fresnel Lenses in fact, is processed into bossing and the anti-convex Fresnel Lenses shape that this comes of recessed part with jog shown in Figure 1 17 at effective diameter φ.
That is, the core of the Fresnel Lenses shape that is made of jog 17 among Fig. 6 becomes recessed part, but in the present embodiment, forms the Fresnel Lenses shape of core projection.Compare with recessed with core, by adopting projection, because therefore average thickness that can the reducer crystal layer can improve the speed of voltage responsive when focus is switched.
Then, form nesa coating (ITO film) on the surface of jog 17, with it as the 1st transparency electrode 13.On the 1st transparency electrode 13, be coated with polyimide film (not shown) again, make its thickness be about 50nm, carry out sintering then, friction orientation is carried out along X-direction in the polyimide film surface handle, as alignment films.
In addition, form nesa coating (ITO film) as the glass substrate of the transparency carrier 12 of transparency electrode 14 on behind the polyimide film of the about 50nm of coating film thickness, carry out sintering, the friction orientation processing is carried out along X-direction in the polyimide film surface.The binding material that to sneak into the interval control material of diameter 15 μ m more thereon passes through printing and forms figure, forms sealing 15, and it is overlapped with transparency carrier 11, carries out crimping, and making transparency electrode interval G is the dummy cell of 15 μ m.
Then,, seal this inlet, use as liquid crystal lens element shown in Figure 6 from inlet (not shown) the injection liquid crystal 16 of dummy cell.
This liquid crystal 16 adopts has ordinary refraction index n 0(=1.507) reach very optical index n eThe nematic crystal of the positive anisotropy specific inductive capacity of (=1.705).In addition, with the plane parallel of the orientation of liquid crystal molecule and transparency electrode 13 and 14 and along the recessed part of the liquid crystal 16 filling jogs 17 of the consistent even orientation of X-direction.The relative dielectric constant ε of liquid crystal 16 LCThe relative dielectric constant ε of long axis of liquid crystal molecule direction //Be 15.2, the relative dielectric constant ε ⊥ of liquid crystal molecule short-axis direction is 4.3, has positive anisotropy specific inductive capacity.In addition, the specific insulation ρ of liquid crystal 16 LCFor more than or equal to 10 10Ω cm.In addition, phase-plate 22 is made equally with example 1.
Transparency electrode 13 and 14 to the liquid crystal lens element 20 that obtains like this connects AC power 18, add frequency f=1kHz apart from the shape alternating voltage.Owing to be equivalent to the condition of the Case2 shown in the 1st example, that therefore distributes to liquid crystal (layer) 16 applies voltage V LCThe ratio V that applies voltage V with respect to transparency electrode 13 and 14 LC/ V is according to the thickness d of jog shown in Figure 5 17 FAnd the bed thickness d of liquid crystal (layer) LCRelation with formula (5) generates the corresponding voltage distribution of the Fresnel Lenses shape V that forms with jog 17 LCIts result, for rectilinearly polarized light incident light with X-axis plane of polarization, so the thickness d of jog 17 FDistribution cause that the difference OPD of the optical length between transparency electrode distributes like that by shown in the following formula.Because the core of Fresnel Lenses shape is a projection, therefore become the different description form of formula (6) with the recessed situation of expression.
[mathematical expression 13]
OPD＝n(V LC[d F])×(G-d F)
-n(V LC[d])×(G-d)-n s×(d-d F)
Thickness d by the film formed jog 17 of SiOxNy FAccording to distributing to zero from d, for the difference OPD of the optical length of the core of Fresnel Lenses shape according to from zero OPD to following formula dDistribute:
[mathematical expression 14]
OPD d＝{n(V LC[d])-n s}×d
-{n(V LC[d])-n(V)}×G
When not applying voltage between transparency electrode, because V=V LC[d]=0, n (0)=n e, so the difference OPD of optical length dBecome the value of following formula.
OPD d＝(n e-n s)×d
＝0.238×2.94
＝0.70μm
Apply voltage V, then OPD if increase between transparency electrode dReduce, there is OPD in the wavelength X=66nm for DVD uses dBecome+λ, zero ,-λ apply voltage V -1, V 0, V + 1(V -1＜V 0＜V + 1).Therefore, apply voltage V if switch -1, V 0, V + 1, the plane wave that then is incident to the wavelength X=660nm of liquid crystal lens element 20 becomes γ, the OPD zero that is equivalent to Fig. 3, the transmission corrugated of β respectively.That is, with applying voltage V -1Generation is equivalent to the lens corrugated of the negative magnification shown in Fig. 4 (C), with applying voltage V 0Generation is equivalent to the transmission corrugated of the no magnification shown in Fig. 4 (B), with applying voltage V + 1Generation is equivalent to the transmission corrugated of the positive amplification ratio shown in Fig. 4 (A).
At the light emitting side configuration condenser lens of liquid crystal lens element 20, according to applying voltage V -1, V 0, V + 1Corresponding switching focusing point position, confirmed the action of the varifocal liquid crystal lens element of three numerical value, at each focus point position configuration aperture diaphragm and photodetector, change between the transparency electrode of liquid crystal lens element 20 apply voltage V the time, Figure 14 shows that the mensuration example of the emergent light of liquid crystal lens element 20 with respect to the focusing efficiency of the incident light of the very light polarization light of wavelength X=660nm.
Applying voltage V -1In 0 to 1.2V scope, become negative magnification (concavees lens), applying voltage V 0In the 1.6V scope, become no magnification (no lensing), applying voltage V + 1In 2.5 to 3V scopes, become positive amplification ratio (convex lens).In addition, focusing efficiency less than 100% reason be depart from the optimum value of jog machining shape with at the different a plurality of reflection losses at the interface of refractive index, this is can be improved.
In addition, owing to refractive index n by the film formed jog 17 of the SiOxNy of homogeneous refractive index material sOrdinary refraction index n with liquid crystal 16 oEqual in fact, so when the ordinary light polarized light is incident to liquid crystal lens element 20, constantization of transmission corrugated.For the incident light of ordinary light polarized light, and the Wavelength-independent that applies voltage and incident light between the transparency electrode of liquid crystal lens element 20, can access 98% the high-transmission rate that the transmitted wave face does not change (no magnification).
Identical with [example 2], this liquid crystal lens element 20 is contained on the optic probe device 70 of the 6th example shown in Figure 11, carry out the record reproducing of the DVD CD of individual layer and bilayer.
When the individual layer DVD CD with 70 couples of cover thickness 0.60mm of this optic probe device carries out record reproducing, be V if establish the voltage that applies of liquid crystal lens element 0About=1.6V, then incident light utilizes object lens 5 to focus on information recording layer effectively.
In addition, for the DVD-dual layer CD, be V if establish the voltage that applies of liquid crystal lens element 20 -1(1V), then incident light focuses on the information recording layer of cover thickness 0.63mm, if the facility making alive is V + 1About (=3V), then incident light focuses on the information recording layer of cover thickness 0.57mm.No matter the calculated value of the remaining RMS corrugated aberration of which kind of situation becomes smaller or equal to 3m λ [rms].
Below, for the CD of cover thickness from 0.56mm to 0.64mm, adopt with liquid crystal lens element 10 apply voltage V 0, V -1, V + 1During the transmission corrugated of corresponding generation, represent the result of calculation of the RMS corrugated aberration that is left with Figure 15.
Therefore, cover thickness be 0.56mm in the scope of 0.585mm, apply voltage V by setting + 1, cover thickness be 0.585mm in the scope of 0.615mm, apply voltage V by setting 0, again cover thickness be 0.615mm in the scope of 0.64mm, apply voltage V by setting -1Thereby last respectively RMS corrugated aberration is reduced to approximately smaller or equal to 20m λ [rms].
In addition, in order to follow the tracks of, object lens 5 along the radial direction of CD D move ± during the 0.3mm left and right sides, though produce eccentricly with liquid crystal lens element 20, because corresponding generation aberration therewith not, so focus point does not degenerate yet.
Therefore, by liquid crystal lens element 20 added voltages are switched to V 0, V -1, V + 1Thereby, realize that the DVD CD D to individual layer and bilayer can carry out the optic probe device of stable record reproducing.
In addition, in the light time of these liquid crystal lens element 20 its wavelength of incident base, for example CD being used the 790nm wavelength band, become the rectilinearly polarized light of ordinary light polarized light by employing for the liquid crystal in the liquid crystal lens element 20 16, thereby constantization of transmission corrugated when not applying voltage, can access high-transmission rate, therefore better.
Industrial practicality
Liquid crystal lens element of the present invention, can be used as according to applying voltage and the focal length of a plurality of focal lengths of corresponding switching switching lens, particularly in the CD with the different individual layer of overburden cover and double-deck information recording layer being recorded and/or resets, owing to can be used as the liquid crystal lens element of proofreading and correct the spherical aberration that comprises the magnifying power component that produces, therefore when liquid crystal lens element and object lens are eccentric, do not produce aberration, so can be used for to alleviate the restriction of configuration, with the integrated optic probe device as small units of the formation such as light source and photodetector and spectroscope etc.
In addition, the Japanese patent application of quoting the basis that becomes the application's claim of priority here is willing to that 2004-026685 number (on February 3rd, 2004 was held Room application perhaps to Japan) and Japanese patent application be willing to the content of whole instructionss of 2004-230606 number (on August 6th, 2004 is to Japan's special permission Room application), adopts the content as instructions announcement of the present invention.

Claims (9)

1. a liquid crystal lens element has variable focal length, it is characterized in that having:
The a pair of transparency carrier that has transparency electrode respectively;
Between the transparency electrode separately that this a pair of transparency carrier has, apply the voltage bringing device of voltage;
Jog, it forms with transparent material and the optical axis that has for liquid crystal lens element has the serrated crosssection shape of rotational symmetry or the jagged cross sectional shape of approximate stairstepping, forms on the transparency electrode of this jog in described each transparency electrode simultaneously; And
At least the liquid crystal of the recessed part of the described jog of filling,
Wherein, according to utilizing described voltage bringing device to be applied to the size of the voltage between described transparency electrode, make the actual refractive index respective change of described liquid crystal, described liquid crystal adopts has ordinary refraction index n oReach very optical index n e, simultaneously the actual refractive index of liquid crystal layer according to the size of the described voltage that applies at n oTo n eThe numerical value of scope between the liquid crystal material that changes, and the direction of orientation with the liquid crystal molecule when not applying voltage in liquid crystal layer all along the characteristic of specific direction orientation, simultaneously
The transparent material of described jog is for unusual light polarization light incident light refractive index n to be arranged at least sTransparent material, refractive index n sValue at n oWith n eBetween, and the refractive index n of described transparent material sSatisfy the relation of following formula:
|n e—n s|≦|n e—n o|/2
Simultaneously, the depth d of the recessed part of described jog is in the scope of following formula for the light wavelength λ that sees through described liquid crystal:
(m—0.25)·λ/|n e—n s|≦d
≦(m+0.25)·λ/|n e—n s｜
In the formula, m=1,2 or 3, and m determines the number of the changeable focal length of described liquid crystal lens element, wherein, and n o≠ n e, n s≠ n o, n s≠ n e
2. liquid crystal lens element comprises:
Liquid crystal lens element as claimed in claim 1; With
Form incorporate phase-plate with liquid crystal lens element as claimed in claim 1, this phase-plate is the odd-multiple of pi/2 for the phase differential of the described light of wavelength X.
3. liquid crystal lens element comprises:
Liquid crystal lens element as claimed in claim 1; And
Be stacked in the phase-plate on the liquid crystal lens element as claimed in claim 1.
4. a liquid crystal lens element is characterized in that,
Comprise two liquid crystal lens elements as claimed in claim 1 that are stacked in together.
5. a liquid crystal lens element is characterized in that, comprising:
Be stacked in together liquid crystal lens element as claimed in claim 1, polarizability diffraction element and phase-plate successively.
6. optic probe device, have the light source of the light that penetrates wavelength X, the photodetector that will focus on object lens on the optical recording media from the emergent light of this light source, will utilize this object lens focusing and utilize the light of described optical recording media reflection to carry out the spectroscope of beam split and detect the light of described beam split, it is characterized in that
In the light path between described light source and described object lens liquid crystal lens element as claimed in claim 1 is set.
7. an optic probe device has the ejaculation wavelength X 1And wavelength X 2Light light source, will focus on the object lens on the optical recording media from the emergent light of this light source and detect the photodetector utilize this object lens focusing and to utilize the light of described optical recording media reflection, it is characterized in that,
In the light path between described light source and described object lens liquid crystal lens element as claimed in claim 1 is set, and as the described wavelength X that is incident to described liquid crystal lens element 1And wavelength X 2Light, described liquid crystal lens element adopts the mutually perpendicular rectilinearly polarized light bundle of plane of polarization, wherein, λ 1≠ λ 2
8. optic probe device as claimed in claim 6 is characterized in that,
Described optical recording media has the overlayer of coverage information recording layer, and described optic probe device writes and/or reads the optical recording media that this tectal thickness differs from one another.
9. optic probe device as claimed in claim 7 is characterized in that described optical recording media has the overlayer of coverage information recording layer, and described optic probe device writes and/or reads the optical recording media that this tectal thickness differs from one another.
CNB2005800035419A 2004-02-03 2005-02-02 Liquid crystal lens element and optical head device Expired - Fee Related CN100492505C (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP2004026685 2004-02-03
JP026685/2004 2004-02-03
JP230606/2004 2004-08-06

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CN103605246B (en) * 2013-11-22 2016-05-18 深圳市华星光电技术有限公司 The manufacture method of a kind of liquid crystal lens, liquid crystal indicator and liquid crystal lens
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