JP2013113938A - Patterned retardation film, image display device, mold for manufacturing patterned retardation film, and method for manufacturing patterned retardation film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a patterned retardation film capable of effectively avoiding degradation of picture qualities in relation to a three-dimensional image display employing a passive system, and to provide an image display device using the patterned retardation film, a mold for manufacturing the patterned retardation film, and a method for manufacturing the patterned retardation film.SOLUTION: In a patterned retardation film 1, fluctuations in a width of a buffer region C between a region (A) for a right eye and a region for left eye are decreased. For this purpose, a mold for manufacturing a patterned retardation film is formed by producing a rugged pattern in one direction entirely on a surface of a base material of the mold, masking the base material with a resist film, forming a rugged pattern in the other direction, and then removing the resist film; and in this process, the film thickness of the resist film is controlled in order to decrease the above fluctuations.

Description

  The present invention relates to a pattern retardation film applied to a three-dimensional image display by a passive method.

  Conventionally, flat panel displays have been mainly two-dimensional displays. However, in recent years, flat panel displays capable of three-dimensional display have attracted attention, and some are also commercially available. Further, there is a tendency that future flat panel displays are capable of three-dimensional display, and flat panel displays capable of three-dimensional display are being studied in a wide range of fields.

  In order to perform three-dimensional display on a flat panel display, it is usually necessary to selectively provide a right-eye image and a left-eye image in some manner, respectively, to the viewer's right eye and left eye. As a method for selectively providing a right-eye video and a left-eye video, for example, a passive method is known. This passive three-dimensional display method will be described with reference to the drawings. FIG. 7 is a schematic diagram showing an example of a passive three-dimensional display using a liquid crystal display panel. In the example of FIG. 7, pixels that are consecutive in the vertical direction of the liquid crystal display panel are sequentially and alternately assigned to a right-eye pixel that displays a right-eye image and a left-eye pixel that displays a left-eye image. And the image data for the left eye, and thereby the image for the right eye and the image for the left eye are simultaneously displayed. In this way, the screen of the liquid crystal display panel is alternately divided into a region for displaying a right-eye image and a region for displaying a left-eye image by a strip-shaped region having a short side in a vertical direction and a long side in a horizontal direction. Will be.

  Furthermore, in the passive method, a pattern retardation film is disposed on the panel surface of the liquid crystal display panel, and the light emitted by the linearly polarized light from the right-eye and left-eye pixels is converted into circularly polarized light having different directions for the right-eye and left-eye. . Therefore, in the pattern retardation film, two types of band-like regions in which the phase axis direction (direction in which the refractive index is maximized) are orthogonal are sequentially formed corresponding to the setting of the region in the liquid crystal display panel. As a result, in the passive method, glasses equipped with corresponding polarizing filters are attached, and a right eye image and a left eye image are selectively provided to the viewer's right eye and left eye, respectively. Here, the slow axis direction of the adjacent belt-like region is usually any combination of +45 degrees and −45 degrees, 0 degrees and +90 degrees, or 0 degrees and −90 degrees with respect to the horizontal direction. Is done. In the example of FIG. 7, the long side direction is shown as the horizontal direction in accordance with the name in a normal image display device. In the passive method, the pixels that are continuous in the horizontal direction in FIG. 7 are divided and driven for the right eye and the left eye, and a three-dimensional image is similarly produced even if a pattern retardation film is produced so as to correspond to this. Can be displayed.

  This passive method can also be applied to a liquid crystal display device with a slow response speed, and can also display three-dimensionally with a simple configuration using a pattern retardation film and circularly polarized glasses. Therefore, the passive liquid crystal display device has been attracting a great deal of attention as a center of the future three-dimensional display device.

  The pattern retardation film according to this passive method requires a patterned retardation layer that gives a phase difference to transmitted light corresponding to the allocation of pixels for the right eye and the left eye. This pattern retardation film has not been widely researched and developed yet, and there is no established standard technology.

  With respect to this pattern retardation film, Patent Document 1 discloses a method for forming a retardation layer by forming a photo-alignment film with controlled alignment regulating force on a glass substrate and patterning the alignment of liquid crystals with this photo-alignment film. Is disclosed. Further, Patent Document 2 discloses a method for forming a photo-alignment film in which a fine uneven shape is formed around a roll plate by laser irradiation, and this uneven shape is transferred to control the alignment regulating force in a pattern shape. ing.

  It is desired that such a pattern retardation film is disposed on an image display panel to effectively avoid image quality deterioration. The image quality degradation is caused by crosstalk in which, for example, streaks and unevenness are observed, or light from the image display panel that should be selectively incident on the right eye and the left eye originally leaks to the left eye and the right eye, respectively. In addition, as the degree of crosstalk increases, the stereoscopic effect is lost.

JP 2005-49865 A JP 2010-152296 A

  The present invention has been made in view of such circumstances, and a pattern retardation film capable of effectively avoiding image quality deterioration with respect to image display according to a passive method, and an image display apparatus using the pattern retardation film An object of the present invention is to provide a mold for producing the pattern retardation film and a method for producing the pattern retardation film.

  The inventor has conducted extensive research to solve the above problems, and led to the idea of reducing the variation in the width of the buffer region between the region for the right eye and the region for the left eye in the pattern retardation film, and For this purpose, the substrate having a concavo-convex shape in one direction is masked with a resist film to create a concavo-convex shape in the other direction, and then the resist film is removed, whereby the concavo-convex in the regions for the right eye and the left eye are removed. The idea of controlling the film thickness of the resist film when producing the shape in the manufacturing mold was reached, and the present invention was completed.

    Specifically, the present invention provides the following.

(1) In a pattern phase difference film that gives a phase difference corresponding to the transmitted light of the phase difference layer by patterning the phase difference layer by an alignment regulation force by an alignment film provided on a substrate made of a transparent film material,
In the alignment film,
A first region in which a minute line-like uneven shape is formed in a substantially constant direction and a second region in which a minute line-like uneven shape is formed in a direction different from the first region are in a band shape. Alternately provided
A buffer region where a line-shaped uneven shape is not formed is provided at the boundary between the first and second regions,
A value ΔW / WAV obtained by dividing a change amount ΔW of the width of the buffer area from the average value WAV by the average value WAV with respect to the average value WAV of the buffer area is set to ± 0.5 or less. The

  According to (1), the variation in the width of the buffer region can be kept within a certain range, so that streak and unevenness on the screen due to the variation in the width do not occur, and further due to crosstalk of the left and right amount images. It is possible to make it difficult to visually recognize a reduction in stereoscopic effect, thereby effectively avoiding deterioration in image quality.

(2) In (1), the buffer region is
The width is set to be 2 μm or more and 100 μm or less.

  According to (2), it is possible to reduce the crosstalk by preventing the buffer region from protruding from the light shielding portion between the pixels of the liquid crystal display panel or the like.

(3) Vertically or horizontally continuous pixels are sequentially assigned to right-eye pixels that display right-eye images and left-eye pixels that display left-eye images, and are driven by corresponding image data. As a result, the display screen is alternately divided into a band-like area for displaying the right-eye image and a band-like area for displaying the left-eye image,
The pattern retardation film according to claim 1 or claim 2 emits the light output from the right-eye pixel and the left-eye pixel by giving a corresponding phase difference to the first and second regions, respectively. .

  According to (3), the image display apparatus by a passive system can be provided using the pattern phase difference film which concerns on the structure of Claim 1 or Claim 2.

(4) Production of a patterned retardation film by patterning a retardation layer by an alignment regulating force by an alignment film provided on a substrate made of a transparent film material, and providing a retardation corresponding to the transmitted light of the retardation layer In the mold for
In the alignment film,
A first region in which a minute line-like uneven shape is formed in a substantially constant direction and a second region in which a minute line-like uneven shape is formed in a direction different from the first region are in a band shape. Alternately provided
The mold for producing the pattern retardation film is
By forming the concavo-convex shape according to the first and second regions by transferring the surface shape,
A flat region in which a line-shaped uneven shape is not formed is provided at a boundary between regions corresponding to the first and second regions,
A value ΔW / WAV obtained by dividing the change amount ΔW of the flat region width from the average value WAV by the average value WAV with respect to the average value WAV of the flat region width is ± 0.5 or less. Is set.

  According to (4), the metal mold | die for manufacture of the pattern phase difference film which produces the pattern phase difference film which concerns on Claim 1 can be provided.

(5) In (4),
The flat buffer region is
The width is not less than 2 μm and not more than 100 μm.

  According to (5), the metal mold | die for manufacture of the pattern phase difference film which produces the pattern phase difference film which concerns on Claim 2 can be provided.

(6) In a method for producing a pattern retardation film, in which an uneven film formed on a mold for producing a pattern retardation film is transferred to a transparent sheet material to form an alignment film.
The pattern retardation film is
By patterning the alignment film, a right-eye region that gives a corresponding phase difference to the transmitted light for the right eye and a left-eye region that gives a corresponding phase difference to the transmitted light for the left eye are each strip-shaped. Alternately formed
The method for producing the pattern retardation film is as follows.
A mold manufacturing process for manufacturing a mold for manufacturing the pattern retardation film,
An alignment film manufacturing step of preparing the alignment film by transferring the surface shape of the mold for manufacturing the pattern retardation film,
The mold manufacturing process includes:
A first concavo-convex shape producing step for producing a concavo-convex shape corresponding to the region for the right eye or the left eye on the entire surface of the base material;
A mask making step of patterning by laminating a resist layer on the surface of the base material and producing a mask exposing a portion corresponding to the region for the left eye or the right eye, and
A thin film production process for producing a thin film for producing an uneven shape on the entire surface of the base material in the upper layer of the resist layer;
A second concavo-convex shape producing step for producing a concavo-convex shape corresponding to the region for the left eye or the right eye on the surface of the thin film for producing the concavo-convex shape;
A resist removing step of removing the resist layer together with the thin film for producing the concavo-convex shape thereon, from the surface of the base material,
The resist layer is set to a film thickness of 0.5 μm or more and 4 μm or less.

  According to (6), the base material having a concavo-convex shape formed on the entire surface is masked with a resist film and rubbed or the like, and then the resist film is removed, thereby patterning the concavo-convex shape related to the right eye region and the left eye region. The pattern phase difference film according to claim 1 can be manufactured by controlling the film thickness of the resist layer so as to be manufactured in a mold for manufacturing the phase difference film.

  According to the present invention, the variation in the width of the buffer region can be kept within a certain value range, so that streaks and unevenness due to the variation in the width can be prevented, and further, the crosstalk cannot be visually recognized. As a result, image quality deterioration can be effectively avoided.

It is a figure which shows the pattern phase difference film which concerns on 1st Embodiment of this invention. It is a figure used for the measurement of a buffer area | region. It is a figure which shows the measurement result of FIG. It is a figure where it uses for description of the manufacturing process of the pattern phase difference film of FIG. It is a figure where it uses for description of the manufacturing method of the metal mold | die of FIG. It is a figure which shows the continuation of FIG. It is a figure where it uses for description of the three-dimensional image display by a passive system.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[First Embodiment]
FIG. 1 is a diagram showing a pattern retardation film applied to the image display device according to the first embodiment of the present invention. In the image display device according to the first embodiment, the pixels of the liquid crystal display panel that are continuous in the vertical direction (left-right direction in FIG. 1) are alternately displayed in order of the right-eye pixel and the left-eye pixel. They are distributed to the left-eye pixels that display the video, and are driven by right-eye and left-eye image data, respectively. As a result, the image display apparatus alternately divides the display screen into a band-like region for displaying the right-eye image and a band-like region for displaying the left-eye image, and separates the right-eye image and the left-eye image. Display at the same time. In this image display device, the pattern phase difference film 1 shown in FIG. 1 is disposed on the panel surface of the liquid crystal display panel, and the pattern phase difference film 1 corresponds to light emitted from pixels for the right eye and the left eye, respectively. To give the phase difference. Thereby, this image display apparatus displays a desired three-dimensional image by a passive method.

  Here, in the pattern retardation film 1, an alignment film 3 and a retardation layer 4 are sequentially formed on one surface of a substrate 2 made of a transparent film such as TAC (triacetyl cellulose). The pattern retardation film 1 is formed of a liquid crystal material that is solidified (cured) in a state where the retardation layer 4 retains refractive index anisotropy, and the alignment of the liquid crystal material is patterned by the alignment regulating force of the alignment film 3. To do. In FIG. 1, the orientation of the liquid crystal molecules is exaggerated by an elongated ellipse. By this patterning, the pattern phase difference film 1 is formed in a band shape alternately with the right-eye area A and the left-eye area B sequentially with a certain width corresponding to the pixel assignment in the liquid crystal display panel. A phase difference corresponding to each of the light emitted from the right-eye and left-eye pixels is given.

  In the pattern retardation film 1, after the ultraviolet curable resin 5 is applied to the surface of the substrate 2, minute uneven shapes are formed on the surface of the ultraviolet curable resin 5. In the pattern retardation film 1, the alignment film 3 is formed by the uneven shape on the surface of the ultraviolet curable resin 5. The pattern retardation film 1 is formed by transferring a minute uneven shape produced on the surface of a mold, which will be described later, to produce a minute uneven shape related to the alignment film 3, and the retardation layer is formed by the alignment regulating force due to the uneven shape. 4 is patterned. For this reason, in the alignment film 3, strip-shaped regions respectively corresponding to the strip-shaped regions A and B for the right eye and the left eye are sequentially formed, and minute uneven shapes are respectively produced. Here, the minute concavo-convex shape is formed by a line-shaped (line) concavo-convex shape extending in one direction, and the direction extending in the one direction is one of the right eye region A and the left eye region B. The first region corresponding to the right region and the second region corresponding to the other direction of the right eye region A and the left eye region B are in directions different from each other by 90 degrees, and the extending direction of each region (horizontal direction) 1 and corresponding to the direction connecting the upper right and the lower left in FIG. 1). In addition, in the inclination with respect to the extension direction of each area | region, when the retardation of the base material 2 is so large that it cannot disregard, it is increased / decreased suitably according to the retardation value. Further, since the line-shaped uneven shape is produced by transferring the surface shape of the mold as will be described later, the uneven shape corresponding to the line-shaped uneven shape in the pattern retardation film 1 is also present in this mold. Will be produced. However, deviations in geometric transformations during transfer of uneven shapes from the mold (errors due to conversion from a cylindrical surface to a flat surface, which will be described later), deviations in the extension direction of line-like uneven shapes due to electrostatic fields during transfer (shifts) ) Cannot be ignored as an error (if the direction deviates approximately by 1 to 3 degrees, it may affect the image quality), the extension direction of the uneven shape is corrected in advance on the mold by an amount that offsets this deviation. In addition to the basic structure shown in FIG. 1, the pattern retardation film 1 is provided with an adhesive layer, a separator film, an antireflection film, and the like as necessary.

  In the pattern retardation film 1 of this embodiment, a flat region in which a line-shaped uneven shape is not formed is provided on the alignment film 3 at each boundary between the band-shaped right eye region A and the left eye region B. A buffer region C is provided between the right-eye region A and the left-eye region B by the flat region of the alignment film 3. Here, the buffer region C is provided in order to simplify the manufacturing process of the mold used for the production of the alignment film 3. The configuration relating to the fabrication of this mold will be described in detail later. Further, by providing the buffer region C, the alignment regulating force by the alignment film 3 does not affect each other between adjacent regions, and the disturbance of the retardation layer 4 in each region A and B can be reduced. it can. Furthermore, in the image display device of this embodiment, image quality deterioration is prevented by controlling the width of the buffer region C in the pattern retardation film 1.

  Here, as shown in FIG. 2, the pattern retardation film 1 is disposed between the polarizing filters 6A and 6B constituting the orthogonal Nicol, the inclination of the orthogonal Nicol relative to the pattern retardation film 1 is changed, and the transmitted light is converted into video. Taken with camera 7. With the crossed Nicols tilted by 45 degrees with respect to the pattern retardation film 1, the right and left eye areas A and B are photographed at a black level, while the buffer area C is photographed at a constant luminance level. It was done. As a result, the buffer region C has a flat alignment film 3 without any uneven shape, and transmitted light is transmitted by the retardation layer 4 even though the alignment regulating force is not applied to the alignment film 3. It was found that a phase difference was given to the phase difference between the regions A and B.

  FIG. 3 is a diagram showing luminance levels obtained by extracting one line of the imaging result of the video camera 7 shown in FIG. This one line is a direction crossing the regions A and B. As shown in FIG. 3, in the imaging result, the luminance level rises periodically corresponding to the buffer region C. In this embodiment, the peak value of the luminance level that rises periodically is averaged, and the detected luminance level is normalized so that the average value becomes 1. Further, the normalized luminance level is determined by the threshold value TH, and an area rising above the threshold value TH is defined as a buffer area C. In this embodiment, determination is made by setting the threshold value TH to a value of 0.1. Instead of such normalization and determination by the threshold value TH, determination may be made by setting a threshold value by the average value of the peak values.

  The buffer region C is assigned to a light shielding portion (a so-called black stripe) between pixels that are continuous in the vertical direction of the image display panel. If the width is set smaller than the width of the light shielding portion, the image quality is not affected. It seems not to. However, even when the buffer region C is narrower than the width of the light shielding portion in this way, when the display screen is observed from a distance, the buffer region C may be seen as a streak or uneven shape. As a result, it was found that the image quality deteriorates. Further, for example, when the viewpoint is changed in the up and down direction, crosstalk may be perceived locally, and it has been found that the image quality deteriorates due to this.

  As a result of detailed examination of this cause, it has been found that when the change in the width of the buffer region C in the extending direction becomes severe, unevenness occurs due to the local increase / decrease in crosstalk, and the crosstalk becomes easily visible. Further, it has been found that when the change in the width has the same tendency in the continuous lines, the unevenness is observed as a streak by continuing in the continuous lines. Therefore, in this embodiment, the variation in the width of the buffer region C is reduced by devising the mold for manufacturing the pattern retardation film according to the setting of the regions A, B, and C, thereby reducing the deterioration of the image quality. . More specifically, the average value of the width of the buffer region C is set to WAV, and the value ΔW / WAV obtained by dividing the change amount ΔW from the average value WAV by the average value WAV is set to be ± 0.5 or less. The value ΔW / WAV is preferably set to ± 0.5 or less as described above. However, since the light-shielding portion of the image display panel may be wide, a practically sufficient image quality is ensured. If it can be done, it may be set to ± 0.8 or less. More preferably, ΔW / WAV is set to 0.3 or less and can be widely applied to various image display panels. The change amount ΔW of the width of the buffer region C can be defined by a statistical range of 2σ 2 times the standard deviation, 4σ of the standard deviation 4σ, 6 times the standard deviation 6σ, etc. In this embodiment, , Defined as 6σ 6 times the standard deviation. In addition, the number of data when obtaining 3σ was 10.

  Further, the change in the width is set to a certain value or less, and the maximum value WMAX of the width is set to be 2 μm or more and 100 μm or less. When ΔW is defined as 6σ here, the maximum value WMAX is WAV + 3σ. The reason why the thickness is set to 100 μm or less is to prevent the buffer region C from protruding from the light shielding portion of the image display panel. Therefore, if the upper limit value is set to 100 μm, it can be applied to various liquid crystal display panels. However, the upper limit value varies depending on the width of the light shielding portion in the liquid crystal display panel on which the pattern retardation film 1 is arranged. Can be changed. Further, in this embodiment, the pattern retardation film 1 is used by being attached to the panel surface of the liquid crystal display panel. Therefore, a sufficient amount of misalignment at the time of attachment is ensured to improve productivity. From a viewpoint, a smaller value is desired. On the other hand, the lower limit is determined from the viewpoint of productivity in the roll plate manufacturing process described later. Therefore, the lower limit value may be increased from the viewpoint of preventing the productivity from decreasing.

[Pattern retardation film manufacturing process]
FIG. 4 is a schematic diagram showing a manufacturing process of the pattern retardation film 1. In the manufacturing process 10, the base material 2 is provided by a roll, and the base material 2 is supplied from a supply reel 11. In the manufacturing process 10, an ultraviolet curable resin is applied to the substrate 2 by the die 12. In this manufacturing process 10, the roll plate 20 is a cylindrical mold in which the uneven shape related to the alignment film 3 of the pattern retardation film 1 is formed around. In the manufacturing process 10, the base material 2 to which the ultraviolet curable resin is applied is pressed against the roll plate 20 by the pressure roller 14, and the ultraviolet curable resin is cured by irradiation of the ultraviolet rays by the ultraviolet irradiation device 15. Thereby, the manufacturing process 10 transfers the uneven | corrugated shape formed in the roll plate 20 to the base material 2. FIG. Thereafter, the substrate 2 is peeled from the roll plate 20 by the peeling roller 16, and the liquid crystal material is applied by the die 19. Thereafter, the liquid crystal material is cured by ultraviolet irradiation by the ultraviolet irradiation device 17, and then wound around the take-up reel 18. The pattern retardation film 1 is produced by forming an adhesive layer, an antireflection layer, and the like on the sheet material wound on the take-up reel 18 as necessary, and then cutting it to a desired size. Thereby, the pattern phase difference film 1 is efficiently mass-produced by continuously processing the base material 2 provided by the roll by transferring the concavo-convex shape using the roll plate 20.

[Roll plate manufacturing process]
5 and 6 are diagrams illustrating a manufacturing process of the roll plate 20 which is a mold for manufacturing a pattern retardation film. In FIGS. 5 and 6, regions corresponding to the regions A, B, and C of the pattern retardation film 1 are denoted by reference numerals ARA, ARB, and ARC, respectively. In this manufacturing process, after the surface of the base material 40 is polished and smoothed (FIG. 5A), in the first concavo-convex shape manufacturing process, the first surface is formed by a fine line-shaped concavo-convex shape on the entire surface of the base material 40. The uneven region 42 is formed (FIG. 5B). Here, the base material 40 is a cylindrical metal material corresponding to the outer shape of the roll plate 20. The base material 40 is not particularly limited as long as a later-described resist layer 43 or the like can be laminated so as to be peeled and removed, and various metal materials such as nickel, chromium, titanium, copper, and cobalt, SiO ₂ , DLC ( diamond-like carbon), TiO2, although it can be applied various inorganic oxides such widely etc., from the viewpoint of stacking to be peeled off such as a resist layer 43 to be described later, a metal material, DLC, TiO _2, etc. Are preferable, and nickel, chromium, and DLC are more preferable. In addition, a method in which various metal material layers are formed on the surface by applying a technique such as sputtering may be applied. If carbide, chromium oxide, chromium molybdenum, or nickel chromium molybdenum is applied, the strength can be improved.

  The first uneven region 42 is formed on the surface of the base material 40 by forming a minute uneven shape corresponding to the uneven shape of the right eye region ARA of the alignment film 3. Specifically, in this embodiment, the concavo-convex shape is produced by rubbing, but in the production method of the concavo-convex shape, various production methods can be widely applied, for example, when producing by polishing. it can. The rubbing treatment is performed by rubbing the surface of a base material made of a titanium layer or the like with a group of fibers on the surface while rotating a cylindrical rubbing roll R having a plurality of fibers planted on the surface around a cylindrical axis. As the fiber material, polyester resin, acrylic resin, urethane resin, polyamide resin, nylon resin, polyolefin resin, cellulose resin, or the like is used. The diameter of the fiber is appropriately selected from the range of about 1 to 100 μm. The rubbing process includes a rubbing process in the direction of the inclination of the fibers and a rubbing process in the opposite direction. The dimensions (width and depth) of the line-shaped uneven shape to be formed, the fibers and the base material. An appropriate direction is selected depending on the combination of the materials.

  Subsequently, for the roll plate 20, a mask in which the region ARB corresponding to the left-eye region B is exposed is manufactured by a resist material in a mask manufacturing process. That is, in this step, a positive resist agent is applied to the entire surface, and then exposed and developed to produce a mask that exposes the region ARB corresponding to the left-eye region B. The resist material is not particularly limited, and a negative resist material may be applied. Various methods can be widely applied even in the coating method and the exposure method.

  In this embodiment, by preparing this resist agent, the resist layer 43 is formed with a film thickness of 2 μm, and thereby the width of the buffer region C is maintained in the above-described range.

  Subsequently, as shown in FIG. 6D, in the thin film manufacturing process, a second layer film 44 made of an inorganic material is formed on the entire surface with a thickness of 0.1 μm. As a result, a second layer pattern composed of the second layer film 44 is formed on the surface of the base material 40 not masked by the resist layer 43. The second layer film 44 is formed by applying a metal material such as chromium, titanium, nickel, etc., a metal compound, and DLC by applying, for example, a sputtering method.

  Subsequently, as shown in FIG. 6E, in the second concavo-convex shape manufacturing step, a direction different from the first concavo-convex region 42 (in this embodiment, the rubbing direction of the first concavo-convex region 42 forms an angle of 90 degrees. The entire surface of the second layer film 44 is rubbed to form a concavo-convex shape. Thereafter, as shown in FIG. 6F, in the manufacturing process, in the subsequent resist removing process, the resist layer 43 is removed together with the second layer film 44 as an upper layer thereof, whereby the alignment is performed by two uneven shape forming processes. Concave and convex shapes corresponding to the regions A and B of the film 3 are produced. The concavo-convex shape forms a line shape, and the averaged extension direction coincides with the rubbing direction. The extending direction of the line-shaped unevenness (which is also the longitudinal direction of the line) generally has a normal distribution, but the distribution in the running direction is 3 degrees or less, more preferably 1 degree or less.

  Here, after the uneven shape is formed on the entire surface in this way, when the uneven shape is partially masked with the resist layer 43, it is possible to prevent deterioration in positioning accuracy related to the patterning of the resist layer 43. There is. However, in this case, due to the step between the regions ARA and ARB, a region in which the concave and convex shape cannot be formed by rubbing occurs on both sides of the region ARB, and the region ARC corresponding to the buffer region C is formed by this region. become.

  When the resist layer 43 is made of 5 μm, the width of the region ARC corresponding to the buffer region C changes greatly in the range of 5 to 30 μm. In this case, in the pattern retardation film 1, the width of the buffer region C is changed. It has been found that it is difficult to keep the value ΔW / WAV within the above-mentioned condition range. However, when the resist layer 43 is made of 2 μm as in this embodiment, the width of the buffer region C can be 5 ± 1 μm, and the value ΔW / WAV related to the buffer region C is in the above-described range. Can fit.

  By the way, it is considered that the thinner the film thickness of the resist layer 43, the narrower the width of the region C and the smaller the variation. However, if the thickness of the resist layer 43 is extremely thin, it becomes difficult to remove the resist film 43 together with the upper layer with high accuracy, or the resist layer is easily damaged and peeled off during rubbing. It becomes difficult to create. For this reason, the resist layer 43 needs to secure a film thickness of at least 0.5 μm and needs to be set to a film thickness of 4 μm or less.

  Instead of such a method of controlling the width of the buffer region C by controlling the thickness of the resist layer 43, it is conceivable to control the width of the buffer region C by a pressing force during the rubbing process. However, in the case where the width of the buffer region C is controlled by the pressing force at the time of rubbing as described above, there is a possibility that the resist layer 43 may be damaged by pressing and rubbing with a large pressing force. In this case, the concavo-convex shape is produced even to the portion masked by the resist layer 43. Thus, when the concavo-convex shape is produced by entering other parts, it becomes difficult for the pattern phase difference film 1 to correctly provide a phase difference in the region for the right eye or the left eye. Talk will occur.

  On the other hand, as in this embodiment, by controlling the width of the buffer region C by controlling the thickness of the resist layer 43, the rubbing process is performed with the optimum pressing force for the preparation of the alignment film, and the buffer is formed with a desired width Region C can be produced.

  Incidentally, in this kind of pattern retardation film, there is also a method of producing a retardation by applying a photo-alignment technique. However, in the case of this method, there is a drawback that it is difficult to make the boundary between the region A for the right eye and the region B for the left eye narrow and linear. However, as in this embodiment, when the alignment layer is formed by transfer using a mold and the retardation layer is formed, the boundary between the right eye region A and the left eye region B is narrow. And can be made linearly.

  According to the above configuration, the variation in the width of the buffer region can be kept within a certain value range, so that the streaks and unevenness can be prevented from being observed by observing from a distance, and further, between the left and right images. Cross-talk can be made invisible and pattern retardation film that can effectively avoid deterioration of image quality, image display device using this pattern retardation film, mold for manufacturing this pattern retardation film Can be provided.

  At this time, by setting the buffer area to a certain width, it is possible to prevent image quality deterioration by preventing the buffer area from protruding from the light shielding portion of the image display panel.

  In addition, by masking the base material on which the line-shaped uneven shape generated in one direction on the entire surface is masked with a resist film to form the uneven shape in the other direction, the resist film is removed, so that the regions for the right eye and the left eye are removed. When producing such a concavo-convex shape in a mold for producing a pattern retardation film, it is difficult to see streaks and unevenness by controlling the film thickness of this resist film, and even crosstalk can be visually recognized. A pattern retardation film can be produced so that it cannot do.

[Other Embodiments]
As mentioned above, although the specific structure suitable for implementation of this invention was explained in full detail, this invention can change the structure of the above-mentioned embodiment variously in the range which does not deviate from the meaning of this invention.

  That is, in the above-described embodiment, on the premise of the manufacturing process of removing the resist film after masking the base material having a concavo-convex shape in one direction on the entire surface with a resist film to produce the concavo-convex shape in the other direction. Although the case where the width of the buffer region is controlled has been described, the present invention is not limited to this, and can be widely applied to the case where a pattern retardation film is manufactured using a manufacturing die manufactured by various manufacturing processes. Specifically, the present invention can be widely applied to the case where a manufacturing die is manufactured by alternately manufacturing regions corresponding to the right-eye region A and the left-eye region B to produce uneven shapes.

  In the above-described embodiment, the case where the roll plate is used has been described. However, the present invention is not limited to this, and the present invention can be widely applied to the case where production is performed by sheet processing using a flat plate.

  In the above-described embodiment, the case where the use of the liquid crystal display panel is assumed has been described. However, the present invention is not limited to this, and the present invention can be widely applied to the case where the use of an organic EL panel or a plasma display panel is assumed. In addition, the present invention can be widely applied to the case where the polarizing filter is provided integrally.

DESCRIPTION OF SYMBOLS 1 Pattern phase difference film 2 Base material 3 Orientation film 4 Phase difference layer 5 UV curable resin 6A, 6B Polarizing filter 7 Video camera 10 Manufacturing process 11 Supply reel 12, 19 Die 14 Pressure roller 15, 17 Ultraviolet irradiation apparatus 16 Peeling Roller 18 Take-up reel 20 Roll plate 40 Base material 42 First uneven region 43 Resist layer 44 Second layer film R Rubbing roll

Claims (6)

In the pattern phase difference film that gives a phase difference corresponding to the transmitted light of the phase difference layer by patterning the phase difference layer by the alignment regulating force by the alignment film provided on the base material by the transparent film material,
In the alignment film,
A first region in which a minute line-like uneven shape is formed in a substantially constant direction and a second region in which a minute line-like uneven shape is formed in a direction different from the first region are in a band shape. Alternately provided
A buffer region where a line-shaped uneven shape is not formed is provided at the boundary between the first and second regions,
A value ΔW / WAV obtained by dividing a change amount ΔW of the width of the buffer area from the average value WAV by the average value WAV with respect to the average value WAV of the buffer area is set to ± 0.5 or less. Pattern retardation film. The buffer region is
The pattern retardation film according to claim 1, wherein the width is 2 μm or more and 100 μm or less. The pixels that are continuous in the vertical direction or the horizontal direction are assigned to the right-eye pixels that sequentially display the right-eye video and the left-eye pixels that display the left-eye video, and are driven by the corresponding image data. Thus, the display screen is alternately divided into a band-shaped area for displaying the right-eye video and a band-shaped area for displaying the left-eye video,
The pattern retardation film according to claim 1 or claim 2 emits the light output from the right-eye pixel and the left-eye pixel by giving a corresponding phase difference to the first and second regions, respectively. Image display device. A mold for producing a patterned phase difference film, in which a retardation layer is patterned by an alignment regulating force by an alignment film provided on a substrate made of a transparent film material, and a phase difference corresponding to the transmitted light of the retardation layer is provided. In
In the alignment film,
A first region in which a minute line-like uneven shape is formed in a substantially constant direction and a second region in which a minute line-like uneven shape is formed in a direction different from the first region are in a band shape. Alternately provided
The mold for producing the pattern retardation film is
By forming the concavo-convex shape according to the first and second regions by transferring the surface shape,
A flat region in which a line-shaped uneven shape is not formed is provided at a boundary between regions corresponding to the first and second regions,
A value ΔW / WAV obtained by dividing the change amount ΔW of the flat region width from the average value WAV by the average value WAV with respect to the average value WAV of the flat region width is ± 0.5 or less. Mold for manufacturing the set pattern retardation film. The flat buffer region is
The width | variety is 2 micrometers or more and 100 micrometers or less, The metal mold | die for manufacture of the pattern phase difference film of Claim 4. In the method for producing a pattern retardation film, which forms an alignment film by transferring the concavo-convex shape formed on the mold for production of the pattern retardation film to a transparent sheet material,
The pattern retardation film is
By patterning the alignment film, a right-eye region that gives a corresponding phase difference to the transmitted light for the right eye and a left-eye region that gives a corresponding phase difference to the transmitted light for the left eye are each strip-shaped. Alternately formed
The method for producing the pattern retardation film is as follows.
A mold manufacturing process for manufacturing a mold for manufacturing the pattern retardation film,
An alignment film manufacturing step of preparing the alignment film by transferring the surface shape of the mold for manufacturing the pattern retardation film,
The mold manufacturing process includes:
A first concavo-convex shape producing step for producing a concavo-convex shape corresponding to the region for the right eye or the left eye on the entire surface of the base material;
A mask making step of patterning by laminating a resist layer on the surface of the base material and producing a mask exposing a portion corresponding to the region for the left eye or the right eye, and
A thin film production process for producing a thin film for producing an uneven shape on the entire surface of the base material in the upper layer of the resist layer;
A second concavo-convex shape producing step for producing a concavo-convex shape corresponding to the region for the left eye or the right eye on the surface of the thin film for producing the concavo-convex shape;
A resist removing step of removing the resist layer together with the thin film for producing the concavo-convex shape thereon, from the surface of the base material,
A method for producing a patterned retardation film, wherein the resist layer is set to have a film thickness of 0.5 μm or more and 4 μm or less.

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