JP2007256473A - Liquid crystal lens - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a uniform liquid crystal lens allowed to be easily manufactured and further reducing irregular gaps in a cell. <P>SOLUTION: In the liquid crystal lens functioned as a variable focus lens by arranging a liquid crystal layer between a gap formed by sticking two transparent substrates to each other through a seal, the seal is constituted of arranging a frame-like first seal formed on the outer edge of the transparent substrate and a second seal formed on the inside of the first seal and the outside of a lens area for modulating the phase of the liquid crystal layer, and mixing spacer. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a liquid crystal lens cell, and more particularly, to a liquid crystal lens that is uniform with no gap unevenness in the cell and is resistant to external stress, although it has a simple configuration.

  Conventionally, as a focusing mechanism for changing the focal length or focal position of an optical system, a method of focusing by moving a lens has been widely used. However, this method requires a lens driving mechanism, and thus has a drawback that the mechanism is complicated and a lens driving motor requires a relatively large amount of electric power. In addition, there is a drawback that the impact resistance is generally low. Thus, as a focusing mechanism that does not require a lens driving mechanism, a method of focusing by changing the refractive index of a liquid crystal lens is known. This method using a liquid crystal lens functions as a variable focus lens by changing the refractive index distribution of the liquid crystal lens by changing the voltage (drive voltage) applied to the liquid crystal lens to drive the liquid crystal lens. It is.

  By the way, when a liquid crystal cell is used as a lens, surface accuracy becomes a problem as with other optical components such as a plastic lens and a glass lens. The surface accuracy in the case of a liquid crystal cell is a characteristic value in both flatness, which is a relative value in the effective lens region surface, and uniformity as an absolute value of the in-plane cell gap distribution.

  This liquid crystal cell is constructed by stacking two glass substrates, and after mixing spacers in a thermosetting epoxy-based sealing material that bonds the glass substrates together, the two glass substrates are pressed and fired. By doing so, the cell gap between the glass substrates is regulated. This cell gap is regulated mainly by mixing spacers made of glass fiber and silica beads into the seal and spraying spacers made of plastic beads and silica beads inside the cell (inside the seal that injects liquid crystal). There are two ways.

  Since these glass fibers and silica beads are relatively hard materials, the spacer becomes a support column when the seal is cured by pressure firing between two glass substrates, and the cell gap is regulated by the particle size of the spacer. . On the other hand, plastic beads are a relatively soft material, and are used mainly for the purpose of maintaining a cell gap by acting as a repulsive force when liquid crystal contracts due to temperature or external stress.

  As described above, in order to uniformly regulate the cell gap, it is sufficient to distribute the spacers uniformly at the target locations and use many spacers. However, if there are spacers in the effective lens region, The spacer portion causes the incident light to be transmitted and diffused, and in some cases, diffracted light is generated. Further, since this spacer disturbs the alignment of the liquid crystal around the spacer, aberration is generated in the light incident on the liquid crystal cell, and the characteristics as the liquid crystal lens are deteriorated. That is, if a spacer exists in the effective lens region, a desired refractive index distribution cannot be obtained, and the lens function is hindered.

  In particular, in the case where the cell gap is increased in order to increase the retardation value, the particle size of the spacer increases despite the fact that the effective lens diameter does not change. growing. For this reason, the problem of the above-mentioned transmission diffusion, the problem of diffraction, and the problem of occurrence of aberration due to disorder of alignment become more remarkable.

In order to create a cell gap by mixing glass fiber in the seal, if the ratio of spacers mixed in the seal is increased, the contact area of the seal and the substrate is reduced by that amount, and the adhesive strength of the seal is impaired. It becomes. If the seal is made thicker, it will hinder downsizing. For example, if the cell gap is to be made uniform only with the glass fiber in the seal, when the seal is arranged away from the effective lens region, the cell gap changes as the distance from the vicinity of the seal increases. The surface accuracy is worse.

Therefore, by using a seal in the spacer and the cell in the spacer, as a method for the absence of spacers in yet effective lens area locally performed N ₂ blowing a dispenser after spacer spraying, the skip spacers effective lens area 1 And a second manufacturing method using a metal mask at the time of spacer dispersion to prevent the spacers from being scattered in the effective lens region (see, for example, Patent Document 1).

JP 2000-81600 A (page 4-6, FIGS. 1, 5, 6)

If the spacer in the effective lens region can be surely eliminated by performing N ₂ blow by performing the N ₂ blow by the first manufacturing method, the transmission diffusion problem, the diffraction problem, the aberration due to the alignment disorder, etc. It is possible to eliminate the problem of occurrence of However, in this method, it is impossible to control where the spacers fly, and the flying destination may enter the effective lens area of the same cell or an adjacent cell again, and this phenomenon is not reproducible. . As described above, since the position where the spacer is blown is not reproducible, it is necessary to check whether the spacer exists in the effective lens region after performing N ₂ blow once. If it is in the region, the N ₂ blow must be performed again. In addition, although this method is performed in order to blow off the spacer only in the effective lens area, there is a possibility that the spacer outside the effective lens area may be blown off. That is, since the spacer near the effective lens region is likely to be blown away by N ₂ blow, it is difficult to accurately regulate the surface accuracy of the effective lens region. In this way, it is apparent that this method is difficult to spread the spacers in the vicinity of the effective lens region.

  In the second manufacturing method, the effective lens region is selectively masked using a metal mask, and the spacers are scattered outside the effective lens region, and the effective lens region and the metal mask are first arranged. It is difficult to obtain position accuracy. In addition, the spacer may enter between the metal mask and the glass substrate, and the spacer may exist in the effective lens region. When the mask area is larger than the mask opening, most of the spacers remain on the mask, and the effective usage rate of the spacers is low and wasteful. Further, in order to fix the mask to the effective lens region, a portion for bridging each mask is required, and a spacer cannot be scattered on that portion. In addition, it is necessary to check the remaining spacers in the effective lens region, and there is a problem that the number of processes is greatly increased.

  Therefore, in order to solve the above-mentioned problems, the present invention is easy to manufacture by forming a seal in which a spacer is mixed around the effective lens region instead of the spacer in the cell, and the cell in the cell is easily manufactured. An object is to provide a uniform liquid crystal lens with less gap unevenness.

In order to solve the above-described problems and achieve the object, the liquid crystal lens of the present invention basically adopts the following configuration.
In the liquid crystal lens according to the present invention, in the liquid crystal lens in which a liquid crystal layer is arranged in a gap formed by bonding two transparent substrates through a seal, the seal is provided on an outer edge portion of the transparent substrate. A frame-shaped first seal and a second seal inside the first seal and provided outside the effective lens region for phase modulation of the liquid crystal layer, which functions as a variable focus lens, and contains a spacer It is characterized by having.

  In the liquid crystal lens according to the present invention, the first seal described above has a closed ring shape, and the second seal described above has an opening for injecting liquid crystal into the effective lens region. Is.

  With the above configuration, by injecting the liquid crystal by dropping injection into the effective lens region or outside thereof, the sealing step in the UV curing agent can be omitted, and the liquid crystal is not wasted.

  The liquid crystal lens according to the present invention is characterized in that the first seal and the second seal described above are integrally formed.

  In the liquid crystal lens according to the present invention, the effective lens region described above has a substantially circular shape, and the second seal is formed in a curved shape along the outer shape of the effective lens region. Is.

  By adopting the above configuration, the uniformity of the cell gap of the liquid crystal lens and the generation of astigmatism with respect to light passing through the liquid crystal lens can be minimized.

  Further, in the liquid crystal lens according to the present invention, the above-described second seal is divided into an even number, and the divided pairs of the divided second seals are arranged point-symmetrically with respect to the lens center of the effective lens region. It is characterized by doing.

  With the above configuration, the uniformity of the cell gap and the occurrence of the astigmatism can be minimized.

  The liquid crystal lens according to the present invention is characterized in that the inner wall surface adjacent to the effective lens region in the second seal described above is disposed so as to be equidistant from the lens center in the effective lens region. It is.

  The liquid crystal lens according to the present invention is characterized in that a spacer is mixed in the first seal as well as the second seal described above.

  As in the above configuration, the uniformity of the cell gap can be further improved by mixing a spacer in the first seal in addition to the second seal.

  According to the liquid crystal lens of the present invention, since a spacer for creating a cell gap can be easily arranged in the vicinity of the effective lens region, the cell gap in the effective lens region is significantly improved compared to the conventional configuration. It becomes possible to regulate the cell gap. The spacer arrangement in the vicinity of the effective lens region can be performed in a normal seal forming process, so that a new process is not added and the liquid crystal lens of the present invention can be easily manufactured.

  Further, according to the liquid crystal lens of the present invention, the spacer does not exist in the effective lens region, and the problem of transmission diffusion, the problem of diffraction, and the problem of occurrence of aberration due to orientation disturbance do not occur.

  Exemplary embodiments of a liquid crystal lens cell according to the present invention and an electronic apparatus equipped with the same will be described below in detail with reference to the accompanying drawings.

  First, a configuration example of the liquid crystal lens cell of the present invention will be described. FIG. 1A and FIG. 1B are a cross-sectional view and a front view showing a cell configuration of a liquid crystal lens, respectively.

  As shown in FIG. 1A, the liquid crystal lens 1a according to the present invention includes, for example, pattern electrodes 24, 25, and 26 in which a predetermined pattern is formed on the inner surface of three opposing transparent substrates 12, 13, and 14. 27 are opposed to each other through a seal so that alignment films 18a and 18b for aligning liquid crystals are formed on the pattern electrodes 24 to 27 by a rubbing process.

  The liquid crystal lens 1a is a homogeneous alignment liquid crystal cell in which, for example, p-type liquid crystals 10 and 11 are sealed so that the director direction in which the liquid crystals 10 and 11 are aligned with each other is 90 °. In this figure, the positional relationship in which the director directions of the liquid crystals 10 and 11 are shifted by 90 ° is such that the liquid crystal 10 is directed perpendicular to the paper surface and the liquid crystal 11 is directed from the lower left to the upper right. However, the present invention is limited to this. It is not a thing. In addition, although the liquid crystals 10 and 11 are in homogeneous alignment, they may be twist alignment, bend alignment, splay alignment, or hybrid alignment, or may be n-type liquid crystal and vertical alignment.

  Moreover, the seal | sticker which adhere | attaches the transparent substrates 12-14 is the 1st frame-shaped seal | sticker 15 provided in the outer edge part of the transparent substrates 12-14, as shown to FIG. Between the transparent substrates 12 to 14 so as to follow the shape of the effective lens region 20 that is circular, in the vicinity of the outer side of the effective lens region 20 for phase modulation of the liquid crystals 10 and 11. A second seal 16a in which a spacer 17 for determining a cell gap is mixed is arranged.

  The second seal 16a is divided into two even numbers so that the liquid crystals 10 and 11 are injected and a sealed space is not formed between the first seal 15 and the second seal 16a. They are divided and arranged in a point-symmetrical relationship with respect to the lens center in the effective lens region 20. The first and second seals 15 and 16a disposed between the transparent substrates 12 and 13 and the transparent substrates 13 and 14, respectively, are overlapped at the same position as shown in FIG. Yes. Accordingly, the cell gap between the transparent substrates 12 and 13 and between the transparent substrates 13 and 14 can be made uniform, and the flatness of the cells can be obtained, so that it passes through the liquid crystal lens 1a. Generation of astigmatism with respect to light can be suppressed as much as possible.

  As described above, the second seals 16a in the liquid crystal lens 1a of the present invention are arranged at the same distance from the center of the lens in the effective lens region 20 and the second seals 16a divided into even numbers. Is desirable. If the divided second seals 16a are arranged at different distances from the lens center, or if the odd number of the second seals 16a are arranged irregularly at irregular intervals, they exist in the effective lens region 20. As the surface accuracy of the liquid crystals 10 and 11 decreases, the possibility that aberrations occur in the light passing through the liquid crystal lens 1a increases. In particular, when there are two liquid crystal layers and the position where the second seal 16a is arranged in the first and second layers in a cell using three transparent substrates 12 to 14, the liquid crystal lens 1a At the time of manufacturing, in particular, unevenness occurs in the pressure distribution during pressurization in the bonding process of the transparent substrates 12 to 14, and the surface accuracy of the liquid crystals 10 and 11 is deteriorated. As a result, there is a problem that aberrations are always generated in the light passing through the liquid crystal lens 1a.

Moreover, in FIG. 1 (a) (b), although the glass fiber is used as the spacer 17,
There is no particular limitation, and silica beads, plastic beads, or conductive particles may be used.

  The liquid crystal lens 1a can be manufactured by the following steps. First, using a second seal 16a in which a predetermined amount of spacers 17 are mixed in advance and a first seal 15 in which spacers are not mixed, printing is performed on a transparent substrate by, for example, a screen printing method. Then, the transparent substrates 12 to 14 are overlapped, and the first and second seals 15 and 16a are applied by applying a predetermined pressure while applying heat to the first and second seals 15 and 16a by hot pressing. It hardens | cures and adhesive force increases and it adhere | attaches with the transparent substrates 12-14, maintaining the cell gap of the particle size of the spacer 17. FIG. The first and second seals 15 and 16a may be patterned by a dispenser.

  Thus, by disposing the second seal 16a as a cell gap correction seal in the vicinity of the effective lens region 20 in the cell, the distance between the effective lens region 20 and the spacer 17, and thus the second seal mixed with the spacer 17 is obtained. The distance to 16a can be made the shortest, and cell gap unevenness can be suppressed as much as possible.

  In addition, in this figure (a) (b), although the form which glass fiber mixes as the spacer 17 only in the 2nd seal | sticker 16a was shown, even if the spacer 17 is mixed also in the 1st seal | sticker 15, it may be in one direction. Absent. If the spacer 17 is mixed into the first seal 15 together with the second seal 16a, the area for regulating the cell gap between the transparent substrates 12 to 14 is further increased, and even if external stress is applied, The deformation amount of the transparent substrates 12 to 14 can be reduced.

  Further, when the spacer 17 is mixed only in the second seal 16a and the spacer 17 is not mixed in the first seal 15, the seal printing method prints the second seal 16a on the transparent substrate 12, for example. After the first seal 15 is printed on the transparent substrate 13, the two types of seal materials can be incorporated into the same cell by superimposing the transparent substrates 12 to 14. For this reason, regarding the 1st seal | sticker 15 and the 2nd seal | sticker 16a, not only the presence or absence or the ratio of the mixing of the spacer 17, but a seal material can also be changed.

  When the first seal 15 and the second seal 16a are formed of the same seal material at the same spacer mixing ratio, that is, when the first and second seals 15 and 16a are formed under the same conditions, the transparent substrates 12 and 13 are used. The first seal 15 and the second seal 16a may be printed on only one side.

  For the first seal 15 and the second seal 16a, a thermosetting epoxy resin, a UV curable epoxy resin, or the like can be used. Further, the first seal 15 and the second seal 16a may be formed by combining different materials.

  The shape of the first seal 15 is a quadrangle in FIG. This shape is not particularly limited, but a large number of cells are simultaneously formed in a large size, and in a strip-shaped cell having a plurality of cells arranged in a line, liquid crystal is simultaneously applied to the plurality of cells. When injecting, it is desirable to have a shape that forms a seal along the outer shape of the transparent substrates 12 to 14, but other shapes may be used. That is, by disposing the frame-shaped first seal 15 in the vicinity of the outer edge portions of the transparent substrates 12 to 14, when the liquid crystal is injected into the cell, it is outside the first seal 15 and the transparent substrate. This is because it is possible to prevent liquid crystal accumulation that enters between 12 and 14 by capillary action. When dicing individually from a strip shape with a dicer, etc., in order to prevent adverse effects on surface accuracy due to glass deformation during cutting, chipping, cracking and chipping, a seal is provided at the blade position, not just at the outer edge. Sometimes it comes and cuts.

  Further, in FIG. 1B, the first seal 15 and the second seal 16a are arranged separately without being connected, but the first and second seals 15 and 16a are integrally connected to each other. You may form in. At that time, in order to allow the liquid crystals 10 and 11 to enter the effective lens region 20, it is important to provide a liquid crystal flow path that communicates with the liquid crystal injection port.

  As an injection method for the liquid crystals 10 and 11, after setting an empty cell in the chamber and evacuating it, the liquid crystal injection port provided in the first seal 15 is immersed in the liquid crystal and returned to atmospheric pressure. The liquid crystal lens 1 can be manufactured by a vacuum injection method in which the liquid crystals 10 and 11 are injected into the cell. When this method is employed, it is necessary to secure a liquid crystal injection path (liquid crystal injection port) as described above. Then, after the liquid crystal is injected, a UV curable sealing agent 19 is applied to the injection port, and the sealing material 19 is cured by UV irradiation to seal the liquid crystal injection port. 1a is completed.

  The liquid crystal lens 1a of the present invention can also be manufactured by a liquid crystal dropping injection method using a dispenser or the like. In this case, although not shown, the first seal 15 has a closed ring shape, and the second seal 16 a has a liquid crystal injection port for injecting the liquid crystals 10 and 11 into the effective lens region 20. Thus, when the liquid crystal dropping injection method is employed with the first seal 15 as a closed ring structure, the sealing material 19 is not necessary. Further, if the liquid crystal dropping injection method is adopted, the liquid crystal can be injected only into the region within the seal, so that useless use of liquid crystal is eliminated.

  The arrangement form of the second seal 16a is not particularly limited as long as it is in the vicinity of the effective lens region 20, and may be a linear shape or a point shape, which will be described later, but it follows the outer shape of the effective lens region 20. A curved shape is desirable.

  As described above, it is desirable to provide the second seal 16a as close to the effective lens region 20 as possible, but in general, in the vicinity of the seal, the seal spreads before the components of the seal are cured during pressure firing. In the vicinity of the liquid crystal, the liquid crystal does not align well, and disclination, which is an alignment continuity defect of liquid crystal molecules, may occur. Therefore, a slight margin is provided between the arrangement positions of the effective lens region 20 and the second seal 16a. Better.

  As described above, according to the liquid crystal lens 1a of the present invention, since the spacer 17 for taking out the cell gap can be easily arranged in the vicinity of the effective lens region 20, the cell gap in the effective lens region 20 is Compared to the conventional configuration, the target cell gap can be regulated. In addition, since the arrangement of the spacers 17 in the vicinity of the effective lens region 20 can be performed in a normal seal forming process, no new process is added and the liquid crystal lens 1a of the present invention can be easily manufactured. it can.

  In addition, according to the liquid crystal lens 1a of the present invention, the spacer 17 does not exist in the effective lens region 20, which frequently occurs in the conventional manufacturing method, and the problem of transmission diffusion that frequently occurs in the conventional configuration. In addition, the problem of diffraction and the problem of occurrence of aberration due to disorder of alignment do not occur.

Next, another configuration example of the liquid crystal lens of the present invention will be described. FIG. 2 is a diagram showing another configuration example of the liquid crystal lens of the present invention.
The liquid crystal lens 1b of the present invention in the present embodiment is different in only the shape of the second seal in the configuration example shown above, and the other configurations are the same. Therefore, in the following description, the difference in the present embodiment will be mainly described, and description of other common members will be omitted.

As shown in FIG. 2, the liquid crystal lens 1b of the present invention has four second seals 16b that are substantially linear. This configuration is particularly effective when a smaller liquid crystal lens 1b is used.
If the external size of the liquid crystal lens 1b is reduced and the cell gap is increased, it becomes difficult to form the second seal 16b in a desired circular shape in screen printing as shown in FIG. There is a case. Therefore, as shown in FIG. 2, the liquid crystal lens 1b in the present embodiment is arranged by dividing the substantially linear second seal 16b into an even number (divided into four in this figure). Yes. Thus, by making the shape of the second seal 16b in the liquid crystal lens 1b substantially linear, the uniformity of the cell gap is improved, and the generation of astigmatism with respect to the light passing through the liquid crystal lens 1b is minimized. can do.

Next, a modification of the liquid crystal lens of the present invention shown in FIG. 2 will be described. FIG. 3 is a diagram showing a modification of the liquid crystal lens 1b described above.
The liquid crystal lens 1c of the present invention in this modification has a different shape only in the shape of the first seal 15 in the liquid crystal lens 1c shown in FIG. 2, and the other configurations are the same. Therefore, in the following description, the difference in this modification is mainly demonstrated, and the description about another common member is omitted.

  As shown in FIG. 3, the liquid crystal lens 1c of the present invention has a configuration in which the outer edge of the second seal 16c and the first seal 15 that is equidistant from the center of the lens in the effective lens region 20 are eliminated. It is as. For example, in the liquid crystal lens 1c, in order to establish conduction between the pattern electrodes 24 and 25 or the pattern electrodes 26 and 27 (see FIG. 1A), a first seal 15 mixed with conductive particles and the like, and a spacer It is assumed that the second seal 16c mixed with 17 is used. Then, the collapse state of the seal (cell gap at the position of the first and second seals 15 and 16c) is changed between the first seal 15 and the second seal 16c, and the surface accuracy of the cell is deteriorated. On the other hand, as described above, the liquid crystal lens 1c in the present modification has the first seal 15 that is equidistant with the distance between the lens center and the outer edge of the second seal 16c. The deterioration of surface accuracy can be minimized.

Next, another modification of the liquid crystal lens of the present invention shown in FIG. 2 will be described. FIG. 4 is a view showing another modification of the liquid crystal lens 1b shown in FIG.
In the liquid crystal lens 1d of the present invention in this modification, only the shape of the second seal in the liquid crystal lens 1b shown in FIG. 2 is different, as in the modification described above. The configuration is the same. Therefore, in the following description, the difference in this modification is mainly demonstrated, and the description about another common member is omitted.

  As shown in FIG. 4, the liquid crystal lens 1d of the present invention has a configuration in which two second seals 16d are added to the liquid crystal lens 1c shown in FIG. The second seal 16d disposed above and below the paper surface is connected to and integrated with the first seal 15. The individual second seals 16d are arranged so that all the inner wall surfaces on the lens center side of the second seal 16d are equidistant from the lens center.

  In the liquid crystal lens 1d of the present invention, the spacer 17 must be mixed in the second seal 16d. However, as shown in the first embodiment, the spacer 17 is also added to the first seal 15 as necessary. It does not matter as a mixed form. Thus, by mixing the spacers 17 in both the first and second seals 15 and 16d, the first and second spacers 15 and 16d can be formed simultaneously by one screen printing. The load of the manufacturing process can be reduced. Further, by using the liquid crystal lens 1d in the present embodiment, in addition to the effects of the previous embodiment, it is possible to provide a lens with improved cell gap accuracy compared to the previous embodiment.

  With the configuration of the liquid crystal lenses 1b to 1d described above, in addition to the effects peculiar to the present invention described in the first embodiment, even if the outer size is made smaller, particularly small and the cell gap is thick, The effect can be maintained.

Next, still another configuration example of the liquid crystal lens of the present invention will be described. FIG. 5 is a diagram showing still another configuration example of the liquid crystal lens of the present invention.
The liquid crystal lens 1e in the present embodiment is different only in the shape of the second seal in the liquid crystal lenses 1a and 1b in the first and second embodiments described above, and the other configurations are the same. Therefore, in the following description, the difference in the present embodiment will be mainly described, and description of other common members will be omitted.

  As shown in FIG. 5, the liquid crystal lens 1 e according to the present invention is an outer periphery of the effective lens region 20, and each dot-like second seal is located at an equal distance from the lens center in the effective lens region 20. 16e is arranged. These point-like second seals 16e are arranged so as to be point-symmetric at positions equidistant from the lens center in the effective lens region 20.

  Thus, by arranging a plurality of second seals 16e symmetrically with respect to the center of the lens, in addition to the effects of the first embodiment, the shape of the second seal 16e having the curvature shown in the first embodiment can be obtained. The problem that it is difficult to obtain a desired circular shape in screen printing at the time of forming can be solved. Further, the second seal 16e is divided into point shapes (in the figure, divided into 8 even numbers) so that a seal having a shape close to an arc shape as a collection of points can be easily obtained. It can be formed, and the occurrence of astigmatism with respect to the uniformity of the cell gap and the light transmitted through the liquid crystal lens 1 can be minimized. The liquid crystal lens 1e has a particularly effective configuration when it is necessary to reduce the outer shape of the cell.

Next, still another configuration example of the liquid crystal lens of the present invention will be described. FIG. 6 is a diagram showing still another configuration example of the liquid crystal lens of the present invention.
The liquid crystal lens 1f in the present embodiment differs from the configuration example shown above only in the shape of the second seal, and the other configurations are the same. Therefore, in the following description, the difference in the present embodiment will be mainly described, and description of other common members will be omitted.

  As shown in FIG. 6, the liquid crystal lens 1 f in the present embodiment has a configuration in which the shape of the second seal 16 f disposed outside the effective lens region 20 is a linear shape.

  In this way, by arranging the two second seals 16f to be symmetrical at positions equidistant from the center of the lens in the effective lens region 20, as described in the other embodiments, the effective lens Although the distance from the region 20 to the inner wall of the second seal 16f varies, the cell gap uniformity can clearly be improved as compared with the conventional configuration.

Next, still another configuration example of the liquid crystal lens of the present invention will be described. FIG. 7 is a diagram showing still another configuration example of the liquid crystal lens of the present invention.
The liquid crystal lens 1g in the present embodiment is different from the configuration example shown above only in the shape of the second seal, and the other configurations are the same. Therefore, in the following description, the difference in the present embodiment will be mainly described, and description of other common members will be omitted.

As shown in FIG. 7, the liquid crystal lens 1g in the present embodiment has a configuration in which a first seal 15 and a second seal 16g are integrated. As a method for manufacturing this configuration example, the first and second seals 15 and 16g are integrated from the screen printing point of time, and the first and second seals 15 and 16g are separately formed by screen printing. The first and second seals 15 and 16g are crushed by pressurizing the transparent substrate after the printing, and the seal width is expanded. Since there is no great difference in load, either manufacturing method may be adopted.

  Thus, by using the liquid crystal lens 1g in the present embodiment, the uniformity of the cell gap and the surface accuracy can be obtained as in the previous embodiment.

Next, still another configuration example of the liquid crystal lens of the present invention will be described. FIG. 8 is a diagram showing still another configuration example of the liquid crystal lens of the present invention.
The liquid crystal lenses 1h and 1i in the present embodiment are different from each other only in the shape of the second seal in the configuration example described above, and the other configurations are the same. Therefore, in the following description, the difference in the present embodiment will be mainly described, and description of other common members will be omitted.

  As shown in FIG. 8A, in the liquid crystal lens 1 h in the present embodiment, the second seal 16 is disposed so as to surround the outer periphery of the effective lens region 20 and is separated from the first seal 15. The structural example which has the seal | sticker made into the form made is shown.

  In the present configuration example, the shape of the second seal 16 has a curved surface shape, so that it becomes difficult to obtain a desired seal shape when the outer dimension of the cell is reduced, but as shown in this drawing. Even if the second seal 16 is not divided into a plurality of even numbers, the effects unique to the present invention described in the first embodiment can be obtained.

  Further, as shown in FIG. 8B, in the liquid crystal lens 1i in the present embodiment, the second seal 16 divided into three pieces is provided on the outer periphery of the effective lens region 20 from the lens center to the second seal 16. The distances to the inner wall surfaces may be made equal to each other.

  As shown in FIG. 8B, when the three second seals 16 are arranged on the outer periphery of the effective lens region 20, as in FIG. The effect of can be obtained.

  As described above, the present invention can easily manufacture a uniform liquid crystal lens with less gap unevenness in the cell by forming a seal in which the spacer is mixed around the effective lens region instead of the spacer in the cell. As an optical component to a camera that is mounted on an electronic device, particularly a camera, a digital camera, a movie camera, a camera phone of a camera-equipped mobile phone, a car, etc. It has suitable quality.

  Further, the configuration of the liquid crystal lens of the present invention is applicable not only to a liquid crystal panel functioning as a lens, but also to a liquid crystal optical element used for correcting wavefront aberration that occurs when recording and reproducing an optical disk. It is.

It is sectional drawing and the front view which show the structural example of the liquid-crystal lens concerning this invention. Example 1 It is a figure which shows the other structural example of the liquid crystal lens concerning this invention. (Example 2) It is a figure which shows the modification in the liquid crystal lens concerning this invention. (Example 2) It is a figure which shows the other modification in the liquid crystal lens concerning this invention. (Example 2) It is a figure which shows the further another structural example of the liquid crystal lens concerning this invention. (Example 3) It is a figure which shows the further another structural example of the liquid crystal lens concerning this invention. (Example 4) It is a figure which shows the further another structural example of the liquid crystal lens concerning this invention. (Example 5) It is a figure which shows the further another structural example of the liquid crystal lens concerning this invention. (Example 6)

Explanation of symbols

DESCRIPTION OF SYMBOLS 1a-1i Liquid crystal lens 10, 11 Liquid crystal 12-14 Transparent substrate 15 1st seal | sticker 16a-16i 2nd seal | sticker 17 Spacer 18a, 18b Alignment film | membrane 19 Sealing agent 20 Effective lens area | region 24-27 Pattern electrode

Claims (7)

In a liquid crystal lens in which a liquid crystal layer is arranged in a gap formed by bonding two transparent substrates through a seal,
The seal is
A frame-shaped first seal provided on an outer edge of the transparent substrate;
A second seal inside the first seal and outside the effective lens region for phase-modulating the liquid crystal layer for functioning as a variable focus lens. The characteristic liquid crystal lens. The first seal has a closed ring shape,
The liquid crystal lens according to claim 1, wherein the second seal has an opening for injecting liquid crystal into the effective lens region.   The liquid crystal lens according to claim 1, wherein the first seal and the second seal are integrally formed. The effective lens region has a substantially circular shape,
4. The liquid crystal lens according to claim 1, wherein the second seal is formed in a curved shape along an outer shape of the effective lens region. 5. The second seal is divided into an even number;
5. The liquid crystal lens according to claim 1, wherein the divided pairs of the divided second seals are arranged point-symmetrically with respect to the lens center of the effective lens region. .   6. The inner wall surface adjacent to the effective lens region in the second seal is disposed so as to be equidistant from the lens center in the effective lens region. The liquid crystal lens described in 1.   The liquid crystal lens according to claim 1, wherein the spacer is mixed in the first seal together with the second seal.

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