WO2012043326A1 - Élément optique soumis à un traitement anti-éblouissement - Google Patents

Élément optique soumis à un traitement anti-éblouissement Download PDF

Info

Publication number
WO2012043326A1
WO2012043326A1 PCT/JP2011/071452 JP2011071452W WO2012043326A1 WO 2012043326 A1 WO2012043326 A1 WO 2012043326A1 JP 2011071452 W JP2011071452 W JP 2011071452W WO 2012043326 A1 WO2012043326 A1 WO 2012043326A1
Authority
WO
WIPO (PCT)
Prior art keywords
optical member
image display
light
angle
shape
Prior art date
Application number
PCT/JP2011/071452
Other languages
English (en)
Japanese (ja)
Inventor
貴志 藤井
Original Assignee
住友化学株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 住友化学株式会社 filed Critical 住友化学株式会社
Publication of WO2012043326A1 publication Critical patent/WO2012043326A1/fr

Links

Images

Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/02—Diffusing elements; Afocal elements
    • G02B5/0205—Diffusing elements; Afocal elements characterised by the diffusing properties
    • G02B5/021—Diffusing elements; Afocal elements characterised by the diffusing properties the diffusion taking place at the element's surface, e.g. by means of surface roughening or microprismatic structures
    • G02B5/0231—Diffusing elements; Afocal elements characterised by the diffusing properties the diffusion taking place at the element's surface, e.g. by means of surface roughening or microprismatic structures the surface having microprismatic or micropyramidal shape

Definitions

  • the present invention relates to an optical member subjected to an antiglare treatment.
  • Image display devices such as liquid crystal displays, plasma display panels, cathode ray tube (CRT) displays, and organic electroluminescence (EL) displays are required to have excellent visibility.
  • Factors that impair visibility in conventional display devices include reflection of external light and changes in light intensity depending on the viewing angle.
  • a process for preventing external light from being reflected on the surface of the image display device is performed.
  • the processing performed on the surface of such an image display device includes antireflection processing using interference by the optical multilayer film and prevention of blurring the reflected image by scattering incident light by forming fine irregularities on the surface. It is roughly divided into dazzling treatment.
  • the former non-reflective treatment increases the cost because it is necessary to form a multilayer film having a uniform optical film thickness.
  • the latter anti-glare treatment can be performed at a relatively low cost, it is widely used in applications such as large-sized televisions, personal computers, and monitors.
  • Such an antiglare treatment is realized by imparting an uneven shape to the surface of the display device.
  • a change in light intensity depending on the viewing angle has been pointed out particularly in a liquid crystal display, but is also a phenomenon that occurs in a display device including a polarizing plate as a constituent member, such as an organic electroluminescence (EL) display.
  • EL organic electroluminescence
  • a display device including a polarizing plate as a constituent member such as an organic electroluminescence (EL) display.
  • EL organic electroluminescence
  • the visibility from the horizontal direction is reduced not only in the liquid crystal display and the organic EL display but also in a display device such as a plasma display panel that does not have a polarizing plate.
  • An object of the present invention is to provide an optical member that reduces the reflection of external light and further improves the visibility when the display device is viewed from a direction other than the front.
  • the present inventor uses a surface with a specific inclination angle in the concavo-convex shape of an optical member that is used by being arranged on the viewing side in a display device, and is formed with an concavo-convex shape on the surface on the viewing side. It has been found that a wide range of visibility can be improved by combining them, and the present invention has been completed.
  • the present invention includes the following.
  • An optical member that is arranged and used on the viewing side in a display device and is antiglare treated by forming an uneven shape on the viewing side surface, wherein the refractive index N1 of the optical member is The refractive index N2 is larger than the refractive index N2 of the optical medium on the emission side of the optical member.
  • the inclination angle ⁇ and the refractive indexes N1 and N2 of the concavo-convex shape are expressed by the following formula (1).
  • An optical member having a first surface that satisfies the relationship (2) and a second surface that satisfies the relationship of the following expression (2).
  • the concavo-convex shape has a third surface satisfying the relationship of the formula (2), and the boundary of the third surface and the second surface forms both the top and the valley.
  • the top means that the boundary between the second surface and the third surface adjacent to each other is higher than the center of either the second surface or the third surface.
  • the part means that the boundary between the second surface and the third surface adjacent to each other is at a position lower than the center of either the second surface or the third surface.
  • the inclination angle ⁇ of the third surface is larger than the inclination angle ⁇ of the second surface.
  • “at a high position” means that when the optical member is arranged on the viewing side of the image display member in the display device, the distance from the image display member to the position is long. “There is” means that the distance from the image display member to the position thereof is short when the optical member is arranged on the viewing side of the image display member in the display device.
  • optical member according to any one of [1] to [5], wherein the optical member is an antiglare film.
  • optical member according to any one of [1] to [8], wherein the optical member is used so that a surface opposite to the viewing side surface is in close contact with a light scattering member having light scattering properties.
  • optical member is used so that a surface opposite to the viewing side surface is in close contact with a light scattering member having light scattering properties.
  • a display device comprising: an image display member; and the optical member according to any one of [1] to [9] disposed on a viewing side of the image display member.
  • a liquid crystal display device comprising: an image display member; and the optical member according to any one of [1] to [9] disposed on a viewing side of the image display member.
  • the optical member has the concavo-convex shape, the inclination angle ⁇ , a distance L from the display surface of the image display member to the concavo-convex shape of the optical member, a pixel size PW of the image display member,
  • the display device according to [10] wherein the viewing-side surface is regarded as a flat surface, and a ratio of the projected view obtained by projecting on the flat surface to a total area of the flat surface is 50% or more.
  • the optical member of the present invention reduces the reflection of external light and further improves the visibility when viewing the display device from a direction other than the front.
  • the optical member of the present invention is used by being arranged on the viewing side in a display device, and an antiglare treatment is performed by forming an uneven shape on the viewing side surface.
  • the refractive index N1 of the optical member is larger than the refractive index N2 of the optical medium on the emission side of the optical member.
  • the optical medium on the exit side of the optical member is usually air.
  • the concave-convex shape formed on the viewing-side surface of the optical member is a first in which the inclination angle ⁇ and the refractive indexes N1 and N2 satisfy the relationship of the following expression (1), where ⁇ is the inclination angle of each surface. And a second surface (surface S2) that satisfies the relationship of the following expression (2).
  • Examples of a method for changing the traveling direction of light include a method using refraction.
  • a method using refraction cannot realize a large change in traveling direction, and an optical member made of a material having a refractive index of about 1.5 can actually change the traveling direction only about 20 °. This is because if the direction of travel of light is greatly changed by refraction, the reflectivity at the interface increases, and the light intensity that can be taken out to the viewer side eventually becomes weak.
  • a method involving total reflection is effective as a method of greatly changing the traveling direction of light on the outermost surface.
  • total reflection not only high light extraction efficiency can be realized, but also the light traveling direction can be changed to an angle far from the front direction, which greatly improves visibility even at an angle far from the front direction. It becomes possible to do.
  • the present invention by combining the total reflection surface and another surface, visibility can be greatly improved even at an angle far from the front direction, and visibility in the front direction can be ensured.
  • the relationship of Formula (1) is a condition in which light incident perpendicularly to the reference plane is totally reflected when the viewing side surface of the optical member is regarded as a plane (hereinafter also referred to as “reference plane”).
  • the upper limit value of the relationship of Expression (2) is a condition in which light incident perpendicularly to the reference plane is not totally reflected.
  • the lower limit value of the relationship of formula (2) defines that the tilt angle is greater than 0 °. When the inclination angle is larger than 0 °, good antiglare properties can be achieved.
  • the optical member used by being arranged on the viewing side in the display device includes an antiglare film and a polarizing plate, but is a resin plate or a glass plate for protecting the surface of the image display member. May be.
  • the uneven shape referred to in the present invention can be grasped from the cross section of the optical member.
  • Arbitrary cross sections may have the same concavo-convex shape, one concavo-convex shape may be provided, and the concavo-convex shape may be maintained in the vertical direction of the cross section.
  • the cross-sectional shape in the longitudinal cross section is a shape parallel to the film.
  • FIG. 1 is a schematic diagram showing the inclination angle of the surface of an optical member that has been subjected to antiglare treatment.
  • the inclination angle is defined by a local normal 6 with respect to the main normal direction 5 of the optical member at an arbitrary point P on the surface of the optical member 1 and taking into account the uneven shape 2 there. It means the angle ⁇ .
  • the inclination angle of the concavo-convex shape 2 can be obtained from a cross-sectional shape photographed with a microscope, or from three-dimensional information of a surface shape measured by a device such as a confocal microscope, an interference microscope, an atomic force microscope (AFM), or the like. Can be sought.
  • a plane 3 shown in FIG. 1 is a plane when the viewing side surface of the optical member 1 is regarded as a plane, and is perpendicular to the main normal direction 5 of the optical member.
  • FIG. 2 is a schematic diagram for explaining a method of measuring the inclination angle of the surface irregularity shape.
  • the point of interest A on the virtual plane FGHI indicated by the dotted line is determined, and the points B and B that are substantially symmetrical with respect to the point A in the vicinity of the point of interest A on the x-axis passing therethrough are determined.
  • points C and E are placed almost symmetrically with respect to the point A, and the surface of the optical member corresponding to these points B, C, D, E Determine the upper points Q, R, S, T.
  • A, Q, R, S, and T are selected from coordinate points with measurement data because calculation is easy.
  • orthogonal coordinates in the surface of the optical member are indicated by (x, y), and coordinates in the thickness direction of the optical member are indicated by z.
  • the plane FGHI is parallel to the x-axis passing through the point C on the y-axis and parallel to the x-axis passing through the point E on the y-axis, and to the y-axis passing through the point B on the x-axis. It is a plane formed by the respective intersections F, G, H, and I with a straight line and a straight line passing through the point D on the x-axis and parallel to the y-axis.
  • the surface of the optical member surface is drawn with respect to the plane FGHI.
  • the position of the surface of the optical member is naturally the plane FGHI depending on the position taken by the point of interest A. May come above or below.
  • the inclination angle of the micro area of the obtained surface shape data corresponds to the point P on the actual optical member surface corresponding to the point of interest A and the four points B, C, D, E taken in the vicinity thereof.
  • Polygon 4 plane stretched by a total of five points Q, R, S, T on the actual optical member surface, that is, normal vectors 6a, 6b, 6c, 6d of four triangles PQR, PRS, PST, PTQ. Can be obtained by calculating the polar angle of the average normal vector 6 obtained by averaging.
  • FIG. 3 is a schematic diagram showing a preferable uneven shape of the optical member of the present invention.
  • each convex portion 7 is formed by a surface S11 having an inclination angle of 72 ° and a surface S21 having an inclination angle of 30 °.
  • the refractive index of the optical member is 1.5, the surface S11 satisfies the relationship of the expression (1), and the surface S21 satisfies the relationship of the expression (2).
  • the surface S11 and the surface S21 have different inclination directions, are adjacent to each other so that the boundary forms a top portion, and the shape of the convex portion 7 is an M shape in which a small valley shape is formed at the top.
  • the convex portions having such a shape are continuously arranged.
  • the convex part 7 is a shape which has a symmetrical surface. Since each convex part 7 has such a shape, the visibility can be improved equally at the left and right positions from the center of the display device.
  • the uneven shape has a surface with an inclination angle exceeding 30 °. On an inclined surface exceeding 30 °, the amount of external light reflected in the front direction is restricted by being blocked by the opposing surfaces, so that it is possible to satisfactorily suppress whitening.
  • FIG. 4 is a schematic diagram showing another preferable uneven shape of the optical member of the present invention.
  • each convex portion 8 is formed by a surface S12 having an inclination angle of 72 °, a surface S22 having an inclination angle of 30 °, and a surface S23 having an inclination angle of 15 °.
  • the refractive index of the optical member is 1.5
  • the surface S12 satisfies the relationship of Expression (1)
  • the surfaces S22 and S23 satisfy the relationship of Expression (2). Since the convex part 8 has a shape having a symmetric surface, the visibility can be improved equally at the left and right positions from the center of the display device.
  • this uneven corrugated shape has a surface where an inclination angle exceeds 30 degrees. On an inclined surface exceeding 30 °, the amount of external light reflected in the front direction is restricted by being blocked by the opposing surfaces, so that it is possible to satisfactorily suppress whitening.
  • FIG. 5 is a schematic diagram showing another preferable uneven shape of the optical member of the present invention.
  • each convex portion 9 is formed by a surface S ⁇ b> 13 that satisfies the relationship of Expression (1) and a surface S ⁇ b> 24 that satisfies the relationship of Expression (2).
  • the surface S13 and the surface S24 have the same inclination direction, the boundary is adjacent so as not to form any top or valley, and the convex portion 9 has a small mountain shape at the top. .
  • the convex portions having such a shape are continuously arranged.
  • the convex part 9 is a shape which has a symmetrical surface.
  • FIG. 6 is a schematic diagram showing another preferable uneven shape of the optical member of the present invention.
  • each convex portion 10 is formed by a surface S14 that satisfies the relationship of Expression (1) and a surface S25 that satisfies the relationship of Expression (2).
  • the convex portion 10 has a shape having at least one plane of symmetry.
  • FIG. 7 is a cross-sectional view schematically showing one convex portion 41 in an example of the concavo-convex shape formed on the viewing-side surface of the optical member.
  • the same convex part as the convex part 41 shown in FIG. 7 is continuously arranged in a cross-sectional direction, and comprises an optical member.
  • the convex portion 41 has a shape in which a surface S15, a surface S26, a surface S31, and a surface S32 are connected in order, and the same shape as this shape is connected in line symmetry.
  • the surface S15 is a surface that satisfies the relationship of the above formula (1).
  • the surfaces S26, S31, and S32 are surfaces that satisfy the relationship of the above formula (2). Therefore, the optical member shown in FIG. 7 is an optical member according to the present invention.
  • the surfaces S31 and S32 are adjacent to the surface satisfying the relationship of the expression (2), but are not adjacent to the surface satisfying the relationship of the expression (1).
  • the point P21 forms a maximum height portion in the surface S15 and the surface S26, that is, the top portion.
  • the point P22 is either the top (the maximum height portion in the surface S26 and the surface S31) or the valley (the minimum height portion in the surface S26 and the surface S31). Also does not form.
  • the point P23 is either the top (the maximum height portion in the surface S31 and the surface S32) or the valley (the minimum height portion in the surface S31 and the surface S32). Also does not form.
  • Inclination angle of surface S26 ⁇ Inclination angle of surface S31 ⁇ Inclination angle of surface S32
  • the state of the light incident perpendicularly to the reference plane will be described.
  • light perpendicular to the reference plane enters the surface S15, it is totally reflected. All or a part of the totally reflected light is incident on one of the surface S26, the surface S31, and the surface S32, is refracted on each surface, and is emitted to the emission-side medium.
  • the light incident perpendicularly to the reference plane is directly incident on the surfaces S26, S31, and S32, the light is refracted on each surface and emitted as it is to the exit side medium, but after being totally reflected on the surface S15.
  • the angle formed by the outgoing light with respect to the normal of the reference plane is reduced. Therefore, these emitted lights contribute to the visibility in the front direction.
  • the angle formed by the outgoing light with respect to the normal of the reference plane of the light refracted after being totally reflected by the surface S15 is the largest for the light refracted by the surface S26 due to the inclination angle of each surface.
  • the light with the larger angle formed by the outgoing light beam with respect to the normal of the reference plane contributes to the improvement of visibility in a direction further away from the front direction (perpendicular to the reference plane).
  • FIG. 8 is a cross-sectional view schematically showing one convex portion in an example of the concavo-convex shape formed on the viewing side surface of the optical member.
  • Convex portions identical to the convex portions 42 shown in FIG. 8 are continuously arranged in the cross-sectional direction to constitute an optical member.
  • the convex portion 42 has a shape in which a surface S16, a surface S27, a surface S33, and a surface S34 are connected in order, and the same shape as this shape is connected in line symmetry.
  • the surface S16 is a surface that satisfies the relationship of the above formula (1).
  • the surface S27, the surface S33, and the surface S34 are surfaces that satisfy the relationship of the above expression (2). Therefore, the optical member shown in FIG. 8 is an optical member according to the present invention.
  • the surfaces S33 and S34 are adjacent to the surface satisfying the relationship of the expression (2), but are not adjacent to the surface satisfying the relationship of the expression (1).
  • the point P24 forms the maximum height portion in the surface S16 and the surface S27, that is, the top portion.
  • the point P25 is either the top (the maximum height portion in the surface S27 and the surface S33) or the valley (the minimum height portion in the surface S27 and the surface S33). Also does not form.
  • the point P26 is either the top (the maximum height portion in the surface S33 and the surface S34) or the valley (the minimum height portion in the surface S33 and the surface S34). Also does not form.
  • Inclination angle of the surface S27> Inclination angle of the surface S33> Inclination angle of the surface S34 A description will be given of the progress of light incident perpendicularly to the reference plane on the viewing-side surface of the optical member having such an uneven shape.
  • light perpendicular to the reference plane enters the surface S16, it is totally reflected. All or a part of the totally reflected light is incident on one of the surface S27, the surface S33, and the surface S34, is refracted on each surface, and is emitted to the emission-side medium.
  • the light incident perpendicularly to the reference plane is directly incident on the surfaces S27, S33, and S34, the light is refracted on each surface and output as it is to the output side medium, but after being totally reflected on the surface S16.
  • the angle formed by the outgoing light beam with respect to the normal of the reference plane is small. Therefore, these emitted lights contribute to the visibility in the front direction.
  • the angle formed by the outgoing light beam with respect to the normal of the reference plane of the light refracted after being totally reflected by the surface S16 is the largest for the light refracted by the surface S34 because of the inclination angle of each surface.
  • the light with the larger angle formed by the outgoing light beam with respect to the normal of the reference plane contributes to the improvement of visibility in a direction further away from the front direction (perpendicular to the reference plane).
  • both are shapes having a dent on the upper surface of the convex portion, but in the shape shown in FIG.
  • light having a large angle formed by the outgoing light beam with respect to the normal of the reference plane refracted near the center of the recess may not be extracted outside the recess. Therefore, from the viewpoint of improving the visibility over a wide range, FIG.
  • the shape shown is more preferred.
  • FIG. 9 is a schematic diagram showing a part of one convex portion in an example of the concavo-convex shape formed on the viewing side surface of the optical member.
  • the surface S17 satisfying the equation (1) and the surface S28 satisfying the equation (2) are adjacent so as not to form the top.
  • the boundary between the surface S17 and the surface S28 is a point P35
  • the point P35 is the maximum height portion of the surface S17 and the minimum height portion of the surface S28.
  • light incident perpendicularly to the reference plane enters the surface S17, it is totally reflected. All or part of the totally reflected light is incident on the surface S28.
  • the incident angle on the surface S28 is increased, part or all of the light reflected by the surface S17 and incident on the surface S28 is reflected by the surface S28. It is preferable to determine the inclination angles of the surface S17 and the surface S28 so that the proportion of light reflected by the surface S28 is reduced.
  • FIG. 10 is a cross-sectional view schematically showing a part of one convex portion in an example of the concavo-convex shape formed on the viewing side surface of the optical member.
  • the concavo-convex shape shown in FIG. 10 has the surface S14 that satisfies the formula (1), but the surface S41 adjacent thereto does not satisfy the formula (2) because the inclination angle is 0 ° and is not included in the scope of the present invention. .
  • the boundary between the surface S18 and the surface S41 is a point P36
  • the surface S41 has the same height as the point P36 at any position. In this case, when light incident perpendicular to the reference plane enters the surface S18, it is totally reflected.
  • All or part of the totally reflected light is incident on the surface S41.
  • Part or all of the light reflected by the surface S18 and incident on the surface S41 is refracted by the surface S41 and emitted.
  • the light is reflected here.
  • the surface S41 since the surface S41 is not inclined, the direction of light refraction is easily limited, and thus it is difficult to improve the visibility from various directions. Further, since the surface S41 is parallel to the reference plane, external light is likely to be reflected.
  • the viewing angle widening effect of the present invention can be confirmed by a ray tracing method.
  • Snell's law and Fresnel regarding the refraction angle at the time of transmission are considered in consideration of light transmission and reflection on the surface of the optical member arranged on the viewing side of the image display member, that is, the interface between the optical member and air. The following calculation was performed by taking
  • FIG. 11 is a schematic diagram showing light refraction and reflection at the interface.
  • the medium having the refractive index ni travels from the medium having the refractive index n i to the medium having the refractive index n t
  • the normal vector of both medium boundary lines is v (normal vector v)
  • the unit vector of incident light is i ( Let incident beam vector i).
  • the unit vector of the reflected ray generated when this ray enters the boundary is r (reflected ray vector r), the vector parallel to the transmitted ray is t (transmitted ray vector t), the incident ray vector i and the normal line
  • the angle formed by the vector v is ⁇ 1
  • the angle formed by the reflected light vector r and the normal vector v is ⁇ 1 ′
  • the angle formed by the transmitted light vector t and the normal vector v is ⁇ 2 .
  • an operator “ ⁇ ” between characters that are explicitly shown as vectors, such as v ⁇ i, means an inner product of the vectors.
  • the intensities Ints and Intp of the transmitted light and the reflected light are obtained from the energy transmittance (T p , T s ) and energy reflectance (R p , R s ) obtained from the Fresnel equation and the intensity of the incident light Ints, Intp.
  • the energy transmittance (T p , T s ) and the energy reflectance (R p , R s ) are given by the following equations (9), (10), (11), (12), respectively.
  • incident light conditions incident angle, intensity, etc.
  • refractive index refractive index
  • the light vector, the intensity of transmitted light, and the intensity of reflected light can be calculated.
  • the calculation value distribution can be obtained by repeating this series of calculation operations for all the light rays that are in the calculation region and are directed toward the boundary surface. All light rays include transmitted light and reflected light generated in place of the light after the light emitted from the light source given as the initial condition reaches the boundary of the medium.
  • FIG. 12 is a schematic diagram showing a two-dimensional model used for calculation of the ray tracing method.
  • the periodic boundary 13 is applied to the horizontal calculation region boundary in FIG. Thereby, the result equivalent to having calculated the state where the same convex part 12 continues infinitely can be obtained.
  • the coordinates of the points D1 to D8 in the two-dimensional model are D1 (0, 0), D2 (0, 0.1), D3 (0, 0.6), D4 (A, 0.6 + H), D5 (A + ( B ⁇ R), 0.6 + H ⁇ (1 ⁇ R)), D6 (A + 2 ⁇ (B ⁇ R), 0.6 + H), D7 (2 ⁇ A + 2 ⁇ (B ⁇ R), 0.6), D8 ( 2 ⁇ A + 2 ⁇ (B ⁇ R), 0.1).
  • H 0.500
  • A 0.162
  • B 0.866
  • R 0.300.
  • 100 point light sources were arranged at equal intervals during one period of the structure. This is an array 11 of point light sources.
  • the emission intensity distribution of the point light source was set so that the angle ⁇ at which the intensity was halved was 20 °.
  • the angle dependency of the light intensity emitted from the point light source was determined based on the following calculation with respect to the emission angle B1 (°).
  • FIG. 13 is a diagram showing a calculation result of light intensity in the model shown in FIG.
  • the horizontal axis indicates the angle from the front direction
  • the vertical axis indicates the light intensity of the emitted light normalized so that the maximum value is 1.
  • the dotted line shows the light intensity distribution of a commercially available liquid crystal television (trade name: TH-32LZ85, manufactured by Panasonic Corporation) without the optical member of the present invention as a color luminance meter “BM-5A” (trade name, Co., Ltd.). It is the result measured by Topcon).
  • the solid line represents the light intensity of the emitted light obtained when the optical member of the present invention is mounted, obtained by calculation.
  • the intensity of the emitted light is a calculated value at the light receiving surface 14 in FIG. According to the optical member of the present invention, since a substantially constant light intensity is maintained up to about 45 °, visibility from an angle away from the front is improved as compared with a display device not equipped with the optical member of the present invention. I understand that.
  • the concavo-convex shapes may be regularly arranged or randomly arranged, but are preferably arranged randomly from the viewpoint of moiré or rainbow unevenness due to reflected light.
  • FIG. 14 is a schematic diagram illustrating an example of a pattern in which the uneven shape is a regular array.
  • a metal mold is engraved with a lathe
  • a metal mold for transferring a concavo-convex pattern is obtained by running a cutting tool along a black portion.
  • the engraving can be performed while leaving a flat surface, or all the surfaces can be engraved.
  • FIG. 15 is a schematic diagram showing an example of a pattern in which uneven shapes are randomly arranged.
  • a bandpass filter that is a kind of spatial frequency filter is applied to a random pattern in which the brightness is set randomly by random numbers, and the resulting pattern is binarized as shown in FIG.
  • the method of engraving along the black line part of a pattern is mentioned.
  • a metal mold for transferring a concavo-convex pattern is obtained by running a cutting tool along a black portion. At this time, by adjusting the pressing depth of the cutting tool, the engraving can be performed while leaving a flat surface, or all the surfaces can be engraved.
  • Examples of the material imparting the uneven shape include glass, transparent crystals, and various transparent resins.
  • Examples of the glass include various glasses such as quartz glass, soda glass, white plate glass, blue plate glass and lead glass in addition to BK7 which is optical glass.
  • Examples of the transparent crystal include quartz and sapphire used as a window plate.
  • Examples of transparent resins include triacetyl cellulose (TAC), polymethyl methacrylate resin (PMMA), polycarbonate (PC), polypropylene (PP), vinyl chloride, and polyethylene terephthalate (PET) that are commonly used in liquid crystal displays. Can be mentioned.
  • TAC triacetyl cellulose
  • PMMA polymethyl methacrylate resin
  • PC polycarbonate
  • PET polyethylene terephthalate
  • the material which comprises an optical member may be one type, and many materials may be laminated
  • dye, a pigment, etc. may be contained.
  • polishing, etching, hot pressing, UV embossing, or the like can be used as appropriate.
  • the surface can be shaped by hot pressing.
  • a desired shape can also be obtained by a polishing apparatus or chemical etching.
  • a surface shape may be imparted by making an easy-molding material such as a resin in close contact with the glass surface and performing hot pressing.
  • the surface shape can be formed by polishing and grinding.
  • a resin In the case of a resin, a heat press or casting to a mold, or a UV embossing method in which UV resin curing is coated on the resin and molded by UV curing in a state of pressing the UV curing resin against the mold is also preferable. Can be used.
  • the antiglare treatment in the optical member according to the present invention has a large change in the traveling direction of transmitted light due to refraction on the surface, and depending on the distance between the display surface of the image display member and the uneven shape provided on the viewing side surface of the optical member,
  • the displayed image may appear double or the image may appear blurry.
  • the optical member of the present invention contains fine particles, or the optical member has a light scattering member having light scattering properties. By arranging them closely, it is possible to obtain visibility from a sufficient angle range while suppressing the blurring phenomenon of the display image by obtaining light traveling in various directions in the optical member or in the region close to the optical member.
  • a display device having the same can be realized.
  • the optical member contains fine particles
  • fine particles made of a material having a refractive index different from that of the material constituting the optical member may be used.
  • the diameter of the fine particles is preferably about 1 ⁇ m to 100 ⁇ m, and more preferably 3 ⁇ m to 20 ⁇ m.
  • fine particles for imparting light scattering to the optical member fine particles made of various organic materials and inorganic materials can be used. Examples of the inorganic fine particles include silica fine particles and titania fine particles.
  • organic fine particles examples include fine particles made of polymethyl methacrylate (PMMA) resin (for example, trade names MX series, MR series, and MP series sold by Soken Chemical Co., Ltd.), fine particles made of styrene resin (for example, , A product name SX series sold by Soken Chemical Co., Ltd.), and fine particles made of silicone resin (for example, a fine particle sold under the trade name Tospearl from Momentive Performance Materials Japan GK).
  • PMMA polymethyl methacrylate
  • MX series trade names MX series, MR series, and MP series sold by Soken Chemical Co., Ltd.
  • styrene resin for example, A product name SX series sold by Soken Chemical Co., Ltd.
  • silicone resin for example, a fine particle sold under the trade name Tospearl from Momentive Performance Materials Japan GK.
  • the optical member of the present invention is preferably used in combination with an image display member, and the optical member according to the present invention is arranged on the viewing side of the image display member to constitute a display device.
  • the image display member is a liquid crystal cell, a liquid crystal display device is configured.
  • the optical member of the present invention in the display device has an inclination angle ⁇ , a distance L from the display surface of the image display member to the uneven shape of the optical member, and an image when the inclination angle of each region is ⁇ in the uneven shape. It is preferable that the ratio of the region satisfying the relationship of the following expression (3) with the pixel size PW of the display member is higher. Specifically, the surface on the viewing side of the optical member is regarded as a plane, and the ratio of the projected view obtained by projecting a region having ⁇ satisfying the relationship of Expression (3) onto the plane is 50% of the total area of the plane. The above is preferable.
  • L the distance from the display surface of the image display member to the uneven shape of the optical member
  • PW the pixel size of the image display member.
  • ⁇ ′ arcsin (N 2 ⁇ N 1 ⁇ sin ⁇ ), where N 1 is the refractive index of the optical member, and N 2 is the refractive index of the optical medium on the exit side of the optical member. is there.
  • the distance L represents the maximum value of the distance from the display surface of the image display member to the uneven shape of the optical member. That is, the distance L represents the distance from the display surface of the image display member to the highest portion of the highest convex portion of the optical member.
  • the concavo-convex shape of the optical member is a triangular wave-like shape
  • the inclination angle of each region is constant, but other concavo-convex shapes such as a concavo-convex shape made of a curved surface are regarded as combinations of regions having various inclination angles. be able to.
  • these regions when the proportion of the region satisfying the expression (3) is 50% or more based on the above-mentioned standard, more than half of the light that should be emitted is correctly emitted as crosstalk between pixels. This means that a good display can be obtained.
  • FIG. 16 is a diagram schematically showing how light travels inside the display device.
  • the meaning which the left side of Formula (3) represents is demonstrated using FIG.
  • the display device shown in FIG. 16 includes an image display member 31 and an optical member 32 having an uneven shape on the viewing side surface.
  • each convex portion has an M-shaped shape, similar to the concave-convex shape shown in FIG.
  • the inclination angle of the surface S2 satisfying the relationship of the expression (2) among the two types of surfaces forming the M shape is defined as ⁇ .
  • Light incident on the surface S2 having the inclination angle ⁇ at the incident angle ⁇ ′, refracted, and directed toward the front (emitted from the inclined surface at the emission angle ⁇ ) is a point C2 ′ at which the display surface normal intersects the display surface and L ⁇ tan.
  • the light is emitted from a point P2 ′ separated by ( ⁇ ′).
  • the light refracted by the inclined surface S2 having the inclination angle ⁇ is emitted from a point P1 ′ that is L ⁇ tan ( ⁇ ′) away from the point C1 ′ where the display surface normal intersects the display surface.
  • the distance between the points P1 and P2 is indicated by the left side of the equation (3). It is. When this distance exceeds the pixel size PW, light emitted from different pixels may be mixed on the surface of the optical member, and the display may appear blurred.
  • the concavo-convex convex portion is M-shaped was examined using FIG. 16, this study is also applied to other concavo-convex shapes, that is, the ratio of the region satisfying the expression (3) is The larger the number, the less the display is blurred. That is, in the present invention, the ratio of the region satisfying the relationship of the formula (3) is increased while the surface S1 satisfying the relationship of the formula (1) and the surface S2 satisfying the relationship of the formula (2). It is preferable to form.
  • L represents the distance from the outermost surface on the viewing side of the optical member to the display surface of the image display member.
  • the position of the display surface of the image display member here will be described below.
  • the position of the display surface of the image display unit is the surface position on the viewing side of the color filter.
  • the light emitting space is positioned closest to the viewing side.
  • one pixel is composed of a set of three colors of light of R, G, and B, or four colors of R, G, B, and Y.
  • the size of one pixel in the present invention is a plurality of colors prepared to express one color such as a set of R, G, B, or a set of R, G, B, Y.
  • PW be the size occupied by a set of unit elements. In the case of a display that is black and white or a field sequential display that switches the color of the light source, the PW is often the size of one unit element. When the size of the set of unit elements differs in the vertical and horizontal directions, the smallest value is assigned to PW.
  • the image display member 31 constitutes one pixel by combining each of the R, G, and B unit elements 34.
  • the half-value angle ⁇ 1 , PW, and L in the emitted light intensity angle distribution of the image display member satisfy the relationship of Expression (4).
  • FIG. 17 is a diagram schematically illustrating how light travels inside the display device.
  • the meaning which the left side of Formula (4) represents is demonstrated using FIG.
  • the display device shown in FIG. 17 includes an image display member 31 and an optical member 32 having an uneven shape on the viewing side surface.
  • the distance between the positions P4 and P5 is represented by the left side of Expression (4).
  • this distance exceeds the pixel size PW light emitted from different pixels may be mixed on the surface of the optical member and the display may appear blurred. That is, when Expression (4) is satisfied, it is possible to suppress the light emitted from different pixels from intermingling on the surface of the optical member within an appropriate range, and it is preferable that the display is not blurred.
  • a method for obtaining a half-value angle alpha 1 is decided measurement points on the image display member, the light source luminance from the position that is equidistant from that point color luminance meter "BM-5A" (trade name, manufactured by Topcon Corporation) and the like Is measured, and the angle formed with the normal of the display surface of the image display member where the luminance is half of the peak is obtained.
  • This angle can be regarded as the half-value angle ⁇ 1 in the outgoing light intensity distribution.
  • the position of the color luminance meter “BM-5A” may be set manually, but more accurate information can be obtained by positioning with an arm robot or the like.
  • the half-value angle ⁇ at the position where the viewer is present by the above-described method.
  • a half-value angle ⁇ 1 in a medium between the optical member and the image display member is obtained according to Snell's law.
  • the half-value angles ⁇ 2 and ⁇ 3 in equations (5) and (6) described later can also be obtained in the same manner as the half-value angle ⁇ 1 described above.
  • the optical member of the present invention includes fine particles that scatter light, or when closely disposed with a light scatter member that scatters light in the display device, the optical member emits light from the image display member 31. Even when the half-value angle is small, it is particularly preferable because good visibility can be realized from a sufficiently wide angle from the viewer side.
  • the display device preferably satisfies the following formula (5).
  • T 1 is the thickness of the optical member (the thickness of the highest portion of the convex portion)
  • ⁇ 2 is the half-value angle in the outgoing light intensity angle distribution of the image display member
  • ⁇ 1 is light scattering by the fine particles contained.
  • the light scattering intensity half-value angle of the optical member having a function is represented.
  • FIG. 18 is a diagram schematically illustrating how light travels inside the display device.
  • the meaning which the left side of Formula (5) represents is demonstrated using FIG.
  • the display device shown in FIG. 18 includes an image display member 31 and an optical member 32 having an uneven shape on the viewing side surface.
  • the optical member 32 includes fine particles and has a light diffusion function. Is emitted at half the angle alpha 2 in the emitted light intensity distribution from the display surface of the image display member 31, light scattered by the light scattering intensity half the angle beta 1 in the optical member 32, in the same position P9 of the irregular shape of the optical member 32 Consider two different positions P7 and P8 on the display surface that will be incident. The distance between the positions P7 and P8 is represented by the left side of Expression (5).
  • the display device includes an image display member, a light scattering member that scatters light disposed on the viewing side of the image display member, and the optical member of the present invention that is disposed in close contact with the viewing side of the light scattering member.
  • the display device preferably satisfies the following formula (6).
  • T 2 is a value obtained by adding the thickness of the optical member (the thickness of the highest portion of the convex portion) and the thickness of the light scattering member
  • ⁇ 3 is the angle distribution of emitted light intensity of the image display member.
  • the half value angle, ⁇ 2 represents the light scattering intensity half value angle of the light scattering member.
  • FIG. 19 is a diagram schematically illustrating how light travels inside the display device.
  • the meaning which the left side of Formula (6) represents is demonstrated using FIG.
  • the display device shown in FIG. 19 includes a light scattering member 35 that scatters light and an optical member 32 that is disposed in close contact with the viewing side of the light scattering member 35. Is emitted at half the angle alpha 3 in the emitted light intensity distribution from the display surface of the image display member 31, light scattered by the light scattering intensity half angle beta 2 in the light scattering member 35 is at the position P12 of the irregular shape of the optical member 32 Consider two different positions P10 and P11 on the display surface that will be incident. The distance between the positions P10 and P11 is represented by the left side of Expression (6).
  • a measurement point of a measurement object having a light scattering ability is determined and directed to the point.
  • Measure the light source luminance with a color luminance meter “BM-5A” (trade name, manufactured by Topcon Co., Ltd.) from a position equidistant from that point.
  • BM-5A trade name, manufactured by Topcon Co., Ltd.
  • the position of the color luminance meter “BM-5A” may be set manually, but more accurate information can be obtained by positioning with an arm robot or the like.
  • Example 1 An antiglare film having a slope having an inclination angle of about 72 degrees and an inclination angle of about 30 degrees and having an uneven shape on the surface on the viewing side similar to the optical member shown in FIG. 2 is used as the optical member.
  • the surface shape subjected to the antiglare treatment is obtained by pressing and curing a UV curable acrylic resin against a silicone rubber mold.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Optical Elements Other Than Lenses (AREA)
  • Liquid Crystal (AREA)

Abstract

L'élément optique de l'invention, qui s'installe sur le côté visible d'un dispositif d'affichage, a été soumis à un traitement anti-éblouissement par la réalisation d'une forme ondulée à la surface de son côté visible. L'indice de réfraction (N1) de l'élément optique est supérieur à l'indice de réfraction (N2) d'un support optique situé sur le côté sortie de l'élément optique et, l'angle d'inclinaison de chaque surface étant θ, la forme ondulée présente une première surface dont l'angle d'inclinaison (θ) et les indices de réfraction (N1, N2) satisfont à la relation de la formule (1) ci-après, et une seconde surface dont l'angle d'inclinaison (θ) et les indices de réfraction (N1, N2) satisfont à la relation de la formule (2) ci-après: N1 × sinθ > N2 (formule 1); 0 < N1 × sinθ < N2 (formule 2).
PCT/JP2011/071452 2010-09-28 2011-09-21 Élément optique soumis à un traitement anti-éblouissement WO2012043326A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2010217329A JP2012073354A (ja) 2010-09-28 2010-09-28 防眩処理が施された光学部材
JP2010-217329 2010-09-28

Publications (1)

Publication Number Publication Date
WO2012043326A1 true WO2012043326A1 (fr) 2012-04-05

Family

ID=45892786

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2011/071452 WO2012043326A1 (fr) 2010-09-28 2011-09-21 Élément optique soumis à un traitement anti-éblouissement

Country Status (3)

Country Link
JP (1) JP2012073354A (fr)
TW (1) TW201229569A (fr)
WO (1) WO2012043326A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPWO2013038633A1 (ja) * 2011-09-15 2015-03-23 三菱電機株式会社 面光源装置及び液晶表示装置

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2014232159A (ja) * 2013-05-28 2014-12-11 住友化学株式会社 防眩フィルム、防眩フィルム製造用金型及びそれらの製造方法
JP2015152659A (ja) * 2014-02-12 2015-08-24 住友化学株式会社 防眩フィルム
JP2015152657A (ja) * 2014-02-12 2015-08-24 住友化学株式会社 防眩フィルム
JP2015152660A (ja) * 2014-02-12 2015-08-24 住友化学株式会社 防眩フィルム
TWI626477B (zh) * 2016-11-04 2018-06-11 茗翔科技股份有限公司 具有溝槽陣列的光學元件及其光源裝置

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS57207235A (en) * 1981-06-15 1982-12-18 Mitsubishi Rayon Co Ltd Renticular lens for screen
JPH07234305A (ja) * 1994-02-21 1995-09-05 Dainippon Printing Co Ltd 面光源用フイルムレンズ及びそれを用いた面光源
JPH08297202A (ja) * 1995-02-28 1996-11-12 Nitto Denko Corp 光拡散板、積層偏光板及び液晶表示装置
JP2001305314A (ja) * 2000-04-19 2001-10-31 Nitto Denko Corp アンチグレア層、アンチグレアフィルムおよび光学素子
JP2002535690A (ja) * 1999-01-14 2002-10-22 ミネソタ マイニング アンド マニュファクチャリング カンパニー 光拡散に適した光学シート
JP2008145550A (ja) * 2006-12-06 2008-06-26 Sony Corp 光学シートおよび表示装置
WO2009078439A1 (fr) * 2007-12-18 2009-06-25 Takiron Co., Ltd. Pellicule optique et unité de rétroéclairage qui utilise celle-ci
WO2010041578A1 (fr) * 2008-10-06 2010-04-15 コニカミノルタホールディングス株式会社 Dispositif d'affichage d'image et casque de réalité virtuelle

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS57207235A (en) * 1981-06-15 1982-12-18 Mitsubishi Rayon Co Ltd Renticular lens for screen
JPH07234305A (ja) * 1994-02-21 1995-09-05 Dainippon Printing Co Ltd 面光源用フイルムレンズ及びそれを用いた面光源
JPH08297202A (ja) * 1995-02-28 1996-11-12 Nitto Denko Corp 光拡散板、積層偏光板及び液晶表示装置
JP2002535690A (ja) * 1999-01-14 2002-10-22 ミネソタ マイニング アンド マニュファクチャリング カンパニー 光拡散に適した光学シート
JP2001305314A (ja) * 2000-04-19 2001-10-31 Nitto Denko Corp アンチグレア層、アンチグレアフィルムおよび光学素子
JP2008145550A (ja) * 2006-12-06 2008-06-26 Sony Corp 光学シートおよび表示装置
WO2009078439A1 (fr) * 2007-12-18 2009-06-25 Takiron Co., Ltd. Pellicule optique et unité de rétroéclairage qui utilise celle-ci
WO2010041578A1 (fr) * 2008-10-06 2010-04-15 コニカミノルタホールディングス株式会社 Dispositif d'affichage d'image et casque de réalité virtuelle

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPWO2013038633A1 (ja) * 2011-09-15 2015-03-23 三菱電機株式会社 面光源装置及び液晶表示装置

Also Published As

Publication number Publication date
TW201229569A (en) 2012-07-16
JP2012073354A (ja) 2012-04-12

Similar Documents

Publication Publication Date Title
US11630250B2 (en) System for use in imaging in air
TWI509322B (zh) Liquid crystal display device
TWI468743B (zh) A light diffusing element and a polarizing plate with a light diffusing element
TWI468741B (zh) A light diffusion element, a polarizing plate with a light diffusion element, and a liquid crystal display device using the same
WO2012043326A1 (fr) Élément optique soumis à un traitement anti-éblouissement
WO2017132579A1 (fr) Rétroéclairage à base d&#39;éléments à faisceaux multiples à vues convergentes
TWI468740B (zh) A light diffusion film, a polarizing plate with a light diffusion film, a liquid crystal display device, and a lighting fixture
US11310478B2 (en) Multiview camera array, multiview system, and method having camera sub-arrays with a shared camera
JP2014515499A (ja) 裸眼立体ディスプレイ用の微細複製フィルム
US20190004237A1 (en) Optical sheet, surface light source device and display device
KR101530452B1 (ko) 광확산 소자 및 광확산 소자를 가진 편광판의 제조 방법, 그리고, 이들 방법으로 얻어진 광확산 소자 및 광확산 소자를 가진 편광판
WO2020092160A1 (fr) Rétroéclairage à vues multiples, unité d&#39;affichage, et procédé comportant des éléments de masque optique
US10466393B2 (en) Display device
JP2015102579A (ja) 導光板、バックライト・ユニット及び液晶ディスプレイ装置
JP2009122371A (ja) 防眩フィルムおよび画像表示装置
WO2011155475A1 (fr) Elément optique ayant subi un traitement anti-reflet
JP2018109687A (ja) 反射スクリーン、映像表示装置
US20220350056A1 (en) System and method for holographic displays
JP2011232367A (ja) 光学シート、面光源装置、透過型表示装置
JP2016090946A (ja) 光学部材、光学部材の製造方法、密着防止層形成用原版の製造方法、面光源装置、映像源ユニット、及び液晶表示装置
JP2012145943A (ja) 液晶ディスプレイ装置用カラーシフト低減光学フィルム及びこれを具備する液晶ディスプレイ装置

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 11828883

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 11828883

Country of ref document: EP

Kind code of ref document: A1