CN101672990A - Zoom liquid crystal lens - Google Patents

Abstract

The invention provides a zoom liquid crystal lens, which comprises a single-layer or multi-layer liquid crystal lens unit, wherein the liquid crystal lens unit utilizes at least two glass substrates with preset thickness, aluminum films, silver films or other light-permeable metal films are respectively arranged on one side or two sides of the glass substrates in an etching mode to form surface alignment electrodes which can be independently controlled, and then the glass substrates are arranged in parallel at intervals to form a chamber space with preset thickness between two adjacent glass substrates for sealing liquid crystal so as to form a layer of liquid crystal lens unit; the arrangement direction, the refractive index and other optical properties of liquid crystal molecules in each liquid crystal lens unit are independently regulated and controlled by voltage, so that the imaging quality is improved, the zooming switching speed is improved, the assembling convenience of the zooming liquid crystal lens is improved, and the thickness of the whole lens and the manufacturing cost can be reduced.

Description

A zoom liquid crystal lens

technical field

The invention relates to a liquid crystal lens, in particular to a zoom liquid crystal lens.

Background technique

Cameras, mobile phone cameras, or stereoscopic image processing devices often use zoom lenses to enlarge or reduce images to form images. Traditional zoom lenses are equipped with multiple lens groups. By moving the lens groups along the optical axis to change the distance between each other, the overall focal length is changed, but the imaging distance is not affected. However, this kind of lens requires a long moving distance of the mirror group, and the distance is nonlinear, so it is very difficult in structural design and control accuracy, and the cost is high and difficult to reduce. In addition, a liquid lens (liquid lens) or a liquid crystal lens (liquid crystal lens, LC lens for short) is used to improve the moving distance of the lens group and reduce the size of the camera. The principle of the liquid lens is composed of an adjustable liquid-filled lens and a solid lens. The lens focal length can be adjusted by changing the shape of the liquid-filled lens (bi-convex or concave-convex) or changing the filling medium with different refractive indices. To achieve the purpose of zooming, such as "Liquid-Crystal Lens-Cells with Variable Focal Length", the author is Susμmu Sato, Japan J. of Applied physics, March 12, 1979; US Patent US2007/0217023. In addition, the principle of the variable focus liquid crystal lens is to apply a non-uniform electric field to a non-uniform liquid crystal layer, or a non-uniform electric field to a uniform liquid crystal layer, or a uniform electric field to a non-uniform liquid crystal layer to produce a gradual refractive index, and Adjust the focal length of the lens to achieve the purpose of zooming, such as the author is Yun-Hsing Fan etc., titled "Liquid crystal microlens arrays with switchable positive and negative focal lengths", Journal of Display Technology, September 2005.

Because liquid crystals have good photoelectric properties and low operating voltage, they have been widely used to make electronically controllable light modulation elements. The existing liquid crystal lens technology, as shown in FIG. 1A, mainly seals liquid crystal molecules 103 between two electrodes 102, uses the voltage distribution change between the two electrodes to change the alignment of liquid crystal molecules, and then changes the flow through the liquid crystal. The optical path characteristics of the lens aperture to achieve the zoom effect. Existing liquid crystal lens electrodes are mostly coated with a layer of ITO transparent conductive film on the surface of glass plate 102 to form ITO electrode 101, and ITO is tin-doped indium oxide (Indiμm Tin Oxide, or Tin-doped IndiμmOxide, referred to as ITO) , due to its excellent electrical conductivity (resistivity can be down to 2×10-4Ω.cm, about 100 times that of the best conductor silver metal) and high visible light transmittance and high infrared light reflectivity, it has been It is developed and used in liquid crystal displays and liquid crystal lenses; its structure, on both sides of the liquid crystal layer, can be composed of two ITO films or one ITO film combined with a metal coating; as shown in Figure 1A, a non-uniform electric field is added to ITO101 , the electric field is applied on the uniform liquid crystal material 103, which will produce a change in the thickness of the contact, change the refractive index of the liquid crystal lens, make the liquid crystal lens change from non-focus to focus, or change its focal length; such as US Patent No. 6,882,390, US7,388,822, US2007/0183293 Taiwan patent TWM327490, Japanese patent JP08-258624, WIPO patent WO/1993/009524, etc. However, due to the high voltage required for the ITO transparent conductive film, when forming a liquid crystal lens (that is, a liquid crystal lens module) with a liquid crystal, its response time is long and the switching speed is slow, so it is not suitable for use in cameras or mobile phone lenses.

For the replacement of ITO materials, the existing technology is to coat aluminum film on the glass substrate and etch a specific aperture as an electrode, as shown in Figure 1B, such as US2007/0183293 and US2007/0182915, which further disclose the use of low-resistance aluminum, Gold, silver or chromium are matched with high-resistance zinc oxide, lead oxide or indium oxide; US2007/0024801 patent discloses the use of gold film as a heat transfer medium; by applying voltage to change the liquid crystal alignment in the aperture To achieve the purpose of zooming; or to fast heat conduction. Due to the use of electrodes with different configurations between the upper and lower layers of liquid crystal molecules, the electric field is different. Although a gradual refractive index can be formed, it also forms an edge attenuation phenomenon, resulting in poor imaging quality, or high operating voltage and poor focusing efficiency. High, focusing efficiency and polarization are dependent, and the range of adjustable focal length is not large enough, so there are still many limitations in use; and in order to solve the above problems, the existing technology often needs to be combined with other traditional lenses to form a composite lens , to compensate the zoom speed and imaging quality, but it also relatively increases the overall thickness and cost, and still cannot effectively solve the problem of zoom switching speed.

Contents of the invention

The main purpose of the present invention is to provide a zoom liquid crystal lens, which utilizes at least two glass substrates with a predetermined thickness, and forms single-sided metal-etched surface alignment electrodes or double-sided metal-etched surface alignment electrodes on the glass substrates by etching electrode; then seal the liquid crystal molecules with the glass substrates at a predetermined distance to form a liquid crystal lens unit; further use the liquid crystal lens unit to form a single-layer or multi-layer zoom liquid crystal lens, and the voltage can be used to independently control the liquid crystal in each liquid crystal lens unit The alignment of molecules produces predetermined optical properties, which are used for the purpose of zooming in devices such as cameras, mobile phone cameras, or stereoscopic image processing.

In order to achieve the above object, the single-layer zoom liquid crystal lens of the present invention includes a single-layer liquid crystal lens unit, and the liquid crystal lens unit is formed by arranging two glass substrates with a predetermined thickness, and an aluminum film, a silver film or other light-transmitting metal films are used to , by etching to form a single-sided metal-etched surface alignment electrode or a double-sided metal-etched surface alignment electrode on the glass substrate to replace the existing ITO (indium oxide doped with tin, Tin-doped Indiμm Oxide, referred to as ITO) an electrode structure formed by a transparent conductive film; wherein, the metal-etched surface alignment electrodes can be symmetrical on both sides (both sides) of the glass substrate, and form surface alignment electrodes with the same alignment pattern; or the surface alignment electrodes The electrodes can be asymmetrical surface alignment electrodes that form different alignment patterns; then the two glass substrates are arranged in parallel at predetermined intervals to form a chamber, and liquid crystal materials are filled in the chamber to form a single-layer liquid crystal lens unit; When a specific voltage is applied to the surface alignment electrodes, the liquid crystal can produce a specific refractive index and optical characteristics; different voltages can produce different refractive indices and optical characteristics, thereby producing the zoom effect of the zoom liquid crystal lens.

Another object of the present invention is to provide a zoom liquid crystal lens, which includes a double-layer or more than three-layer liquid crystal lens unit, and the liquid crystal lens unit is formed by arranging at least two glass substrates with a predetermined thickness. The light-transmitting metal film is etched to form a single-sided metal-etched surface alignment electrode or a double-sided metal-etched surface alignment electrode on the glass substrate; wherein, the metal-etched surface alignment electrodes are on both sides of the glass substrate ( The surface alignment electrodes on both sides) can be symmetrical and form the same alignment pattern; or the surface alignment electrodes can be asymmetrical and form different alignment patterns; then the two glass substrates are arranged in parallel at predetermined intervals, Constitute a chamber, and fill the chamber with liquid crystal material to form a double-layer or multi-layer liquid crystal lens unit; when a specific voltage is applied to the surface alignment electrodes of each layer, the liquid crystal can produce specific refractive index and optical characteristics; for Applying different voltages can produce different refractive indices and optical properties, thereby producing the zoom effect of the zoom liquid crystal lens.

Another object of the present invention is to provide a zoom liquid crystal lens. The surface alignment electrodes formed by metal etching on the glass substrate surface of a single-layer or multi-layer liquid crystal lens unit can be designed as a single-hole or concentric circle alignment pattern. To provide a variety of changes in optical properties such as aperture, refractive index, and focal length.

Another object of the present invention is to provide a kind of zoom liquid crystal lens, to improve the liquid crystal lens that existing ITO forms, because the structure of the liquid crystal lens that existing ITO forms is for the liquid crystal layer both sides, can be two ITO films or One piece of ITO film is combined with one piece of metal coating. Therefore, the surface of the alignment electrode on the surface of the two glass substrates in contact with the liquid crystal is a state of different materials. When a voltage is applied, the drag force ( anchoring force) will have a slight gap, thus affecting the final polarization properties of the liquid crystal lens aperture; in order to improve this phenomenon, one of the characteristics of the present invention is to use surface alignment electrodes of the same material on both sides of the liquid crystal layer, which can be easily adjusted to a good Symmetrical, reducing the problem of liquid crystal lens aperture eccentricity.

Compared with the prior art, the variable-focus liquid crystal lens of the present invention can be matched with single-layer or multi-layer liquid crystal lens units of different layers and different surface alignment electrodes according to the needs of optical design, and the voltage of the liquid crystal lens unit can be individually controlled to generate a refractive index , aperture size and other optical characteristics changes to improve the zoom switching speed and optimize the optical effect and zoom quality of the overall liquid crystal lens module, which can reduce the overall lens thickness and production cost.

Description of drawings

1A and 1B are schematic side views of conventional zoom liquid crystal lenses.

Fig. 2 is a schematic diagram of the appearance of the single-layer liquid crystal lens unit of the present invention.

Fig. 3 is an exploded schematic view of the appearance of the single-layer liquid crystal lens unit of the present invention.

FIG. 4A is a schematic diagram of the electric field action of the surface alignment electrodes (the upper and lower surface alignment electrodes are asymmetrical).

FIG. 4B is a schematic diagram of liquid crystal molecules under the action of the electric field in FIG. 4A .

FIG. 5A is a schematic diagram of the electric field action of the surface alignment electrodes (the upper and lower surface alignment electrodes are symmetrical).

FIG. 5B is a schematic diagram of liquid crystal molecules under the action of the electric field in FIG. 5A .

Fig. 6 is a schematic diagram of the relationship between the refractive index and the incident angle.

7A, 7B, and 7C are schematic diagrams of optical paths when the liquid crystal lens unit (first embodiment) produces different refractive indices in different electric fields.

Fig. 8 is a schematic diagram of manufacturing a double-sided electrode glass substrate.

Fig. 9 is a schematic diagram of the structural side and optical path of the double-layer liquid crystal lens unit (second embodiment) of the present invention.

Fig. 10 is a schematic diagram of the structural side and optical path of the three-layer liquid crystal lens unit (third embodiment) of the present invention.

Description of reference signs: zoom liquid crystal lens-1, 2, 3; glass substrate-10; single-sided electrode glass substrate-10a; double-sided electrode glass substrate-10b; aperture-11; surface alignment electrodes-20, 20a, 20b; Liquid crystal layer-30; spacer-40; metal film-50; photoresist layer-51; photomask-52.

Detailed ways

The above and other technical features and advantages of the present invention will be described in more detail below in conjunction with the accompanying drawings.

The following embodiments of the present invention are described for the main components of the zoom liquid crystal lens of the present invention. Therefore, in terms of the general liquid crystal lens module structure, those of ordinary skill in the art understand that the zoom liquid crystal lens disclosed in the present invention The constituent elements are not limited to the structure of the embodiments disclosed below, that is, the constituent elements of the zoom liquid crystal lens can be changed, modified, or even equivalently changed, for example: the appearance shape design of the zoom liquid crystal lens and There is no limitation, or the alignment pattern of the surface alignment electrodes is also not limited.

4A is a schematic diagram of the electric force lines of a simple electric field. If the upper surface alignment electrode 20a and the lower surface alignment electrode 20b are positively charged and negatively charged respectively, the electric force lines will be non-linear at the edge. After the liquid crystal layer 30 is filled between the surface alignment electrode 20a and the surface alignment electrode 20b, as shown in FIG. The molecules are subjected to an electric field to generate torque. In order to obtain the minimum energy state, the main axis of the liquid crystal molecules in the liquid crystal layer 30 will be aligned parallel to the applied electric field (along the tangential direction of the electric field), forming a specific arrangement to produce specific refractive index and optical properties. Since the structure of the liquid crystal molecules in the liquid crystal layer 30 is anisotropic and has birefringence characteristics, when the light passes through the liquid crystal layer 30, the polarization direction of the light will be related to the main axis of the liquid crystal molecules, and the incident light is in the direction of the orthogonal light The field component causes the liquid crystal molecules to be polarized. For the edge of the electric field (such as the edge of the two electrode lines), in the area outside the influence range of the electric field edge, the electric field forces the direction of the main axis of the liquid crystal molecules, so that the liquid crystal molecules exhibit a refractive index in this electric field. n0; and the electric field lines of force at the edges of the two electric fields will cause the liquid crystal molecules of the liquid crystal layer 30 to change their original main axes, thus forming different refractive indices n1 at the edges of the two electric fields; but at the center of the edges of the two electric fields, the liquid crystal The molecules are not affected by the electric field to change the main axis of the liquid crystal molecules, where the refractive index is n. The change of the refractive index in the Y direction is n0-n1-n-n1-n0, then a refractive index gradient is formed; when electric fields of different intensities are applied to the upper surface alignment electrode 20a and the lower surface alignment electrode 20b , different refractive indices are produced in the Z direction, which can produce zooming when the light passes through.

If the upper layer surface alignment electrode 20a is symmetrical to the lower layer surface alignment electrode 20b, as shown in Figure 5A and Figure 5B, the area outside the range affected by the edge of the electric field is relatively small, and the change in the refractive index in the Y direction is approximately n0- n-n0, a refractive index gradient different from that in FIG. 4B is formed; when electric fields of different intensities are applied to the upper surface alignment electrode 20a and the lower surface alignment electrode 20b, different refractive indices are generated in the Z direction, which can be light Zooming occurs when passing.

Therefore, in the liquid crystal lens unit 1, the polarization direction of the light field is different from the direction of the liquid crystal molecules, and the principle of forming a different refractive index (refractive index gradient) is made into a similar GRIN lens, and the refractive index gradient is changed by applying different external electric fields. Make the incident light inside the liquid crystal lens unit, because of the gradient of the refractive index, the light changes the angle of travel and focuses, as shown in Figures 6, 7A, 7B, and 7C. In Figure 6, for the gradients of different refractive indices, it can be considered as n layers for analysis, and obeys the following relationship of Snell’s law:

n ₁ cos(θ ₁ )=n ₂ cos(θ ₂ )=…n _i cos(θ _i )=…=n _n cos(θ _n ) (1)

Among them, ni is the assumed refractive index of the i-th layer, and 90°-θi is the angle between the normal of the i-th layer light at the interface between the i-th layer and the i+1 layer.

Since the liquid crystal is subjected to different electric fields in the liquid crystal lens unit, the refractive index ni is different, but ni is not easy to measure, the average refractive index n can be used to approximate the refractive index change rate α, and the focal length f can be estimated by the following formula:

$\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; f</span>}}<span\; class="notranslate">\; =</span>\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; no</span>}}\mathrm{<span\; class="notranslate">\; \&alpha;</span>}\mathrm{<span\; class="notranslate">\; sin</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; D.</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span>$

For the liquid crystal layer 30 of a liquid crystal lens unit with a certain thickness D, if different electric field strengths and directions are changed, the refractive index gradient of the liquid crystal lens will be changed (that is, the refractive index change rate α and the average refractive index n will be changed), and different The exit angles, thus forming different focal lengths, as shown in Figures 7A, 7B, and 7C; when applying voltage to the surface alignment electrode 20 for different liquid crystal lens units, the different refractive indices can be changed, and the light can be focused or diverged. A zoom function such as a lens group can be formed.

Furthermore, for the surface alignment electrode 20 on the upper layer of the surface alignment electrode 20a and the lower layer of the surface alignment electrode 20b, it can be set to be symmetrical or asymmetrical, and can also be set as a single-hole alignment pattern, a concentric circle alignment pattern or other optical purpose designs. patterns to create different aperture effects. In order to clearly illustrate the embodiment of the application of the present invention, a single-hole symmetrical surface alignment electrode 20 is used in FIGS. 2 , 3 , 8 to 10 .

first embodiment

Referring to Fig. 2, shown in 3, it is the basic structure of the zoom liquid crystal lens embodiment that the present invention is made of single-layer liquid crystal lens unit, the single-layer zoom liquid crystal lens 1 of the present embodiment, counting from object side, comprises: single-sided The glass substrate 10 (hereinafter referred to as the single-sided electrode glass substrate 10b) with the surface alignment electrode 20, the spacer (spacer) 40, and the liquid crystal layer 30 filled in the chamber formed by the single-sided electrode glass substrate 10b and the spacer 40 and a single-sided electrode glass substrate 10b; wherein, the spacer 40 can be a ring-shaped sheet or several stacked ones; wherein, a surface alignment electrode 20 is attached to the surface of the glass substrate 10, and the surface alignment electrode 20 is The glass substrate 10 is coated with a metal film, such as aluminum, silver, or gold, and the metal is selected as a light-transmitting metal; the metal film is formed by etching. The hole-shaped alignment pattern forms a single-hole aperture 11 ; wherein, after the two glass substrates 10 are combined, the spacer 40 defines the thickness of the gap, that is, the thickness of the liquid crystal layer 30 .

Referring to FIG. 8 , it is a schematic diagram of the yellow light manufacturing process of the alignment electrode 20 on the upper surface of the glass substrate 10. This process diagram only illustrates the schematic diagram of the manufacturing process of the glass substrate 10 with the double-sided surface alignment electrode 20 (hereinafter referred to as the double-sided electrode glass substrate 10a), and The manufacturing process of the alignment electrode 20 on one side of the single-side electrode glass substrate 10 b is also similar, and only one side of the glass substrate 10 has a metal film. First, a layer of metal film 50 is plated on the surface of the glass substrate 10 by deposition or sputtering, and then etched into the desired alignment pattern of the surface alignment electrodes 20 by using a yellow light process; the processing steps are as follows: A photoresist layer 51 is provided on the outside of the metal film 50, and a photomask 52 with a specific alignment pattern is covered on the outside of the photoresist layer 51, and then exposed, developed, rinsed, etched and other related procedures to remove non- For the rest of the photoresist layer and metal film of the surface alignment electrode 20 , only the photoresist layer and metal film corresponding to the surface alignment electrode 20 are kept, and then the photoresist layer 51 is removed to form the surface alignment electrode 20 . If it is desired to make the alignment electrodes 20 on both sides of the glass substrate 10 have a symmetrical alignment pattern, the photomask 52 can be used when the yellow light is made, and the double-sided yellow light process machine can be used to complete the etching once; for Different surface alignment electrodes 20 on both sides use different photomasks 52 , and can be produced by using a single-side photoresist process machine.

Generally speaking, in order to keep the operating voltage from being too high, the ratio of the size of the aperture 11 formed by the single-hole surface alignment electrode 20 to the thickness of the liquid crystal layer 30 is about 2.5 to 1, and the size of the aperture 11 can be from 100 μm to 1 mm; for liquid crystal layers 30 with different thicknesses, spacers 40 with different thicknesses can be used. The liquid crystal material used in this embodiment is a nematic liquid crystal E7, a glass substrate 10 with a thickness of 1 mm is used for the glass substrate 10 on the object side, and a glass substrate 10 with a thickness of 0.5 mm is used for the glass substrate 10 on the image side. The thickness of the liquid crystal layer 30 is D = 120 µm.

When a voltage is applied to the surface alignment electrode 20, an electric field can be generated, thereby changing the refractive index of the liquid crystal layer 30. In this embodiment, the relationship is shown in Table 1 and Figures 2.7A-7C. When it is desired to change the single-layer zoom liquid crystal lens When the focal length is 1, the voltage difference in Table 1 is applied to the surface alignment electrodes 20 on both sides of the glass substrate 10 .

Table I,

Tables 2 to 5 show the focal length f (mm), focal number FNo, and back focal length (BL) (mm) of the single-layer zoom liquid crystal lens 1 for four different focal lengths, for the angle between the incident light and the optical axis on the optical axis Root mean square spot (spot size rms, root-means-square μm), geometric spot size (GEO spot size, Geometric, μm), tangential field curvature (field TAN, Tangential field curvature), sagittal field curvature at each angle of θ (field SAG, Sagittal field curvature), distortion rate (distortion rate)%, at 60 ° TAN modulation transfer function (MTF, modulation transfer function) and 60 ° SAG MTF related data, which can be provided for imaging of devices such as cameras and mobile phones lens used.

Table II

Table three

Table four

Table five

second embodiment

Referring to FIG. 9 , it is the basic structure of an embodiment of the double-layer zoom liquid crystal lens composed of double-layer liquid crystal lens units of the present invention. The double-layer zoom liquid crystal lens 2 of the present embodiment, counting from the object side, includes: a single-sided electrode glass substrate 10b, a spacer 40 and a first layer of liquid crystal layer 30, a double-sided electrode glass substrate 10a, a spacer 40 and a second layer The liquid crystal layer 30 and the single-sided electrode glass substrate 10b; wherein, between the single-sided electrode glass substrate 10b and the double-sided electrode glass substrate 10a, the thicknesses of the two liquid crystal layers 30 are respectively defined by the spacer 40 . When the incident light refracts for the first time through the first layer of liquid crystal layer 30 of the zoom liquid crystal lens 2, and then enters the second layer of liquid crystal layer 30 of the liquid crystal lens unit 2, the second refraction can be generated; The first layer of voltage makes the first layer of liquid crystal layer 30 form a refractive index n1, and controls the second layer of voltage so that the second layer of liquid crystal layer 30 forms a refractive index of n2, and the position of light focus can be calculated through formula (2); in the same way For devices such as cameras or mobile phones, for the zoom requirements of different focal lengths, as long as the voltage of the first layer is controlled to match the voltage of the second layer, the zoom effect can be achieved. Compared with the traditional lens multi-chip combination module, it can be saved. lots of space.

For the convenience of description, in this embodiment, the same liquid crystal layer 30, spacer 40 of the same thickness, glass substrate 10 of the same material and thickness, surface alignment electrodes 20, etc. are used as in the first embodiment; in order to achieve an overall focal length of 0.866mm , then apply a voltage of 2.15V to the first layer of liquid crystal layer 30 (i.e. the first liquid crystal lens unit) to make it produce a focal length of 1.111mm, apply a voltage of 1.49V to the second layer of liquid crystal layer 30 (i.e. the second liquid crystal lens unit) Make it produce focal length and be 2.525mm, table six is when the present embodiment focal length is 0.866mm, for the root mean square spot, geometric spot, tangent field curvature, The relevant data of field curvature of lone vector, distortion rate%, modulation transfer function at 60°TAN and 60°SAG MTF can be used for imaging lenses of cameras, mobile phone cameras and other devices.

Table six

When zooming to an overall focal length of 0.746mm, a voltage of 1.74V is applied to the first liquid crystal layer 30 (i.e. the first liquid crystal lens unit) to produce a focal length of 1.720mm, and the second liquid crystal layer 30 (i.e. the first liquid crystal lens unit) Two liquid crystal lens units) apply a voltage of 2.31V to produce a focal length of 1.013mm. Table 7 is when the focal length of this embodiment is 0.746mm, for the root mean square light spot, geometric light spot, tangential field curvature, sagittal field curvature, and distortion rate % under the angle θ between the incident light and the optical axis on the optical axis , The relevant data of 60° TAN modulation transfer function and 60° SAG MTF can be used for imaging lenses of cameras, mobile phone cameras and other devices.

Table Seven

third embodiment

Referring to FIG. 10 , it is the basic structure of an embodiment of the three-layer zoom liquid crystal lens 3 composed of three-layer liquid crystal lens units in the present invention. The three-layer zoom liquid crystal lens 3 of the present embodiment, counting from the side of the object, includes: a single-sided electrode glass substrate 10b, a spacer 40 and a first layer of liquid crystal layer 30, a double-sided electrode glass substrate 10a, a spacer 40 and a second layer Liquid crystal layer 30, double-sided electrode glass substrate 10a, spacer 40, third layer liquid crystal layer 30, and single-sided electrode glass substrate 10b; between the single-sided electrode glass substrate 10b and the double-sided electrode glass substrate 10a, with The spacers 40 respectively define the thicknesses of the three liquid crystal layers 30 . When the incident light passes through the first layer of liquid crystal layer 30 of the three-layer zoom liquid crystal lens 3 and produces the first refraction, then enters the second layer of liquid crystal layer 30 of the zoom liquid crystal lens 3 to generate the second refraction, and then enters The third liquid crystal layer 30 of the liquid crystal lens unit 3 produces the third refraction; when the first layer voltage is controlled to make the first layer liquid crystal layer 30 form a refractive index n1, and the second layer voltage is controlled to make the second layer The liquid crystal layer 30 forms a refractive index n2, controls the voltage of the third layer to make the third layer liquid crystal layer 30 form a refractive index n3, and the position where the light is focused can be calculated through formula (2); the same is used in cameras or mobile phone cameras, etc. On the device, for the zoom requirements of different focal lengths, as long as the voltage of the first layer is controlled, the voltage of the second layer and the voltage of the third layer are matched, the zoom effect can be achieved. Compared with the traditional lens multi-chip combination module, it can save a lot of space.

As can be seen from the above, the present invention has at least the following advantages:

(1) The zooming liquid crystal lens of the present invention uses the liquid crystal lens unit 10 to perform the zooming action, without adding a mechanical movement mechanism, and the whole module can be made lighter, thinner and shorter.

(2) In the zoom liquid crystal lens of the present invention, the surface alignment electrode 20 structure of an aluminum film (or other suitable light-transmitting metal such as a silver film) is used between each liquid crystal layer 30 to replace the existing ITO electrode, which can reduce costs.

(3), the zoom liquid crystal lens of the present invention, wherein the surface alignment electrode 20 of the liquid crystal lens unit can be designed by different alignment patterns such as single hole shape, concentric circle shape, and the different electric field patterns produced by the surface alignment electrode 20 can produce different apertures Large and small effects, and then combined into a zoom liquid crystal lens through a single-layer or multi-layer liquid crystal lens unit, can constitute a practical zoom lens for a camera, mobile phone camera or image processing device.

The above description is only illustrative, rather than restrictive, to the present invention. Those of ordinary skill in the art understand that many modifications and changes can be made without departing from the spirit and scope defined by the following appended claims. Or equivalent, but all will fall within the protection scope of the present invention.

Claims (8)

1, a kind of Zoom liquid crystal lens, it comprises individual layer liquid crystal lens unit; The glass substrate of two predetermined thickness of described individual layer liquid crystal lens unit by using, make single-side electrode glass substrate or double-face electrode glass substrate, again two plate electrode glass substrates are arranged in parallel with preset space length by distance piece, the room space that forms one deck predetermined thickness between the two plate electrode glass substrates is constituted to form a liquid crystal layer for sealing liquid crystal up for safekeeping; It is characterized in that:

Described single-side electrode glass substrate or described double-face electrode glass substrate are provided with surperficial orientation electrode, described surperficial orientation electrode is provided with the metal film of a light-permeable on the surface of described glass substrate, form predetermined orientation pattern by etching mode again, and the electrode on each glass electrode substrate is controlled independently to impose voltage respectively;

When the surperficial orientation electrode to two glass electrode substrates imposes specific voltage, in the liquid crystal layer of regulation and control liquid crystal lens unit the row of liquid crystal molecule to, and then produce specific refractive index.

2, a kind of Zoom liquid crystal lens comprises double-deck liquid crystal lens unit; The glass substrate of three predetermined thickness of described double-deck liquid crystal lens unit by using, make single-side electrode glass substrate or double-face electrode glass substrate, again described three plate electrode glass substrates are arranged in parallel with preset space length by distance piece, the room space that forms one deck predetermined thickness between adjacent two glass electrode substrates is respectively constituted to form two-layer liquid crystal layer for sealing liquid crystal up for safekeeping; It is characterized in that:

Described single-side electrode glass substrate or described double-face electrode glass substrate are provided with surperficial orientation electrode, described surperficial orientation electrode is provided with the metal film of a light-permeable on the surface of described glass substrate, form predetermined orientation pattern by etching mode again, and the electrode on each glass electrode substrate is controlled independently to impose voltage respectively;

When the surperficial orientation electrode to adjacent two glass electrode substrates imposes specific voltage, the row who regulates and control liquid crystal molecule in the liquid crystal layer of each layer liquid crystal lens unit to, and then produce specific refractive index.

3, a kind of Zoom liquid crystal lens comprises that the liquid crystal lens unit constitutes more than three layers; The described glass substrate of four above predetermined thickness of liquid crystal lens unit by using more than three layers, make single-side electrode glass substrate or double-face electrode glass substrate, again described each glass electrode substrate is arranged in parallel with preset space length by distance piece, the room space that forms one deck predetermined thickness between adjacent two glass electrode substrates is respectively constituted to form two-layer liquid crystal layer for sealing liquid crystal up for safekeeping; It is characterized in that:

Described single-side electrode glass substrate or described double-face electrode glass substrate are provided with surperficial orientation electrode, described surperficial orientation electrode is provided with the metal film of a light-permeable on the surface of described glass substrate, form predetermined orientation pattern by etching mode again, and the electrode on each glass electrode substrate can be controlled independently to impose voltage respectively;

When the surperficial orientation electrode to adjacent two glass substrates imposes specific voltage, regulate and control in the liquid crystal layer of each layer liquid crystal lens unit in liquid crystal molecule row to, and then produce specific refractive index.

As claim 1,2 or 3 described Zoom liquid crystal lens, it is characterized in that 4, set light-permeable metal film is aluminium or silver on the described glass baseplate surface.

5, as claim 1,2 or 3 described Zoom liquid crystal lens, it is characterized in that, surperficial orientation electrode on the described glass baseplate surface is to plate layer of metal film with sedimentation earlier on the surface of described glass substrate, on described metal film, be coated with a photoresist layer again, on described photoresist layer, be covered with the mask layer of a specific orientation pattern again, again through develop, etching program to be to remove the photoresist layer and the metal film of non-electrode part, and keep the photoresist layer and the metal film of electrode part, remove photoresist layer again and form.

6, as claim 1,2 or 3 described Zoom liquid crystal lens, it is characterized in that, surperficial orientation electrode on the described glass baseplate surface is to plate layer of metal film with sputtering method earlier on the surface of glass substrate, on described metal film, be coated with a photoresist layer again, on described photoresist layer, be covered with the mask layer of a specific orientation pattern again, again through develop, etching program to be to remove the photoresist layer and the metal film of non-electrode part, and keep the photoresist layer and the metal film of electrode part, remove photoresist layer again and form.

As claim 1,2 or 3 described Zoom liquid crystal lens, it is characterized in that 7, the orientation pattern of described surperficial orientation electrode is the single hole shape.

As claim 1,2 or 3 described Zoom liquid crystal lens, it is characterized in that 8, the orientation pattern of described surperficial orientation electrode is a concentric circles.

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