JP6488870B2 - Manufacturing method of optical lens - Google Patents

Description

  The present invention is used for manufacturing an optical lens in which two optical members are bonded with an optical functional member (for example, a hologram optical element) interposed therebetween, an image display device and a head mounted display including the optical lens, and the optical lens, for example. The present invention relates to an optical sheet in which a hologram photosensitive material is held on a resin sheet, and an optical lens manufacturing method using the optical sheet.

  In recent years, with the advent of advanced information society accompanying the development of information transmission media, it has been strongly desired to output various information efficiently. Among various information, image information occupies a very high ratio, and wearable devices with high portability that do not choose a place where the information is used play an important role in performing advanced information processing activities.

  In image output, expectations for wearable displays are increasing. In particular, in the expansion from the amusement field to the industrial field, there is an increasing expectation for a so-called transmissive wearable display that can observe the background (external world) while observing a display image (virtual image) through an optical lens. In the transmissive wearable display, by further increasing the transparency of the optical lens, the background and the display image can be observed without a sense of incongruity, and visual stress can be greatly reduced. Therefore, it is important to increase the transparency of the optical lens.

  The optical lens is configured, for example, by forming a hologram optical element on one joint surface of two optical members and then joining the two optical members with a joint member (adhesive). The hologram optical element cuts out a predetermined area from an optical sheet (hologram sheet) holding a hologram photosensitive material, and pastes the cut out area (hereinafter also referred to as a cut-out area) on the joint surface of the optical member. It is produced by exposing a hologram photosensitive material.

  Here, the shape of the cutout region is generally rectangular. For example, Patent Document 1 discloses a technique in which a sheet is cut into a rectangular shape to cut out a frame-shaped hologram, and the frame-shaped hologram is attached to a plate-shaped member such as glass.

  Further, for example, Patent Document 2 discloses a technique for replicating a hologram on a hologram sheet by attaching a hologram sheet to a hologram master and exposing the hologram sheet. The shape of the hologram replication area in the hologram sheet is rectangular in plan view. When this technique is applied to the production of the optical lens, a rectangular hologram replication region is cut out in the shape (rectangular shape) and attached to the joint surface of the optical member.

Japanese Patent Laid-Open No. 10-109811 (refer to Claims 1 and 2, paragraphs [0025] to [0046], FIG. 5, FIG. 6, etc.) JP-A-8-52749 (see claims 1 to 4, paragraphs [0017], FIG. 7, etc.)

  In the transmissive wearable display, when increasing the transparency of an optical lens, the transparency of a plurality of optical members (for example, prisms) constituting the optical lens and a bonding member (for example, an adhesive) that joins the plurality of optical members is increased. In addition to this, it is important to reduce the remaining amount of bubbles in the joint surface generated in the optical lens assembly process. This is because the bubbles affect vision and lead to deterioration of permeability (decrease in visibility).

  In the assembly process of the optical lens (hereinafter also referred to as the lens assembly process), bubbles are generated when the optical sheet is stuck to the optical member (sticking process) and when the two optical members are joined (joining process). Hereinafter, a mechanism for generating bubbles in each process will be described.

  In the optical sheet attaching step, an optical sheet for exhibiting an optical function such as a mirror or a hologram is attached to a prism as an optical member. For example, as shown in FIG. 27, when the optical sheet 100 is composed of three layers of the base material 101, the joining member 102, and the hologram photosensitive material 103, the blade from the hologram photosensitive material 103 side to the half of the thickness of the base material 101. The base material 101 is bent at an acute angle to the opposite side of the hologram photosensitive material 103 and the cut region (the region inside the cut in the bonding member 102 and the hologram photosensitive material 103) is peeled off from the base material 101. To do. Then, the separated cut-out region is attached to the prism from the bonding member 102 side. Note that portions other than the cut-out region in the bonding member 102 and the hologram photosensitive material 103 of the optical sheet 100 remain on the base material 101 side at the time of peeling, but the illustration thereof is omitted in FIG. The hologram photosensitive material 103 affixed to the prism is then exposed to become an optical functional member 103 ′ (see FIG. 29).

  Here, when the shape of the cut region of the optical sheet 100 is a rectangular shape as in the past, the cut region is peeled from the base material 101 from the end of the cut region in the long side direction. (Because it is easier to peel from the edge in the short side direction). For this reason, at the time of peeling, as shown in FIG. 28, stress is applied to the entire end portion of the cutout region (only the hologram photosensitive material 103 is shown in the figure). That is, the stress at the time of peeling is applied to the entire short side of the cut region. As a result, the joining member 102 in the cut-out region is pulled toward the base material 101 on the entire short side that is the peeling start portion, and the joining member 102 is likely to partially peel from the hologram photosensitive material 103. When the cut region is attached to the prism in such a partially peeled state, bubbles are caught in the partially peeled portion between the bonding member 102 and the hologram photosensitive material 103 in the cut region.

  Even when the optical sheet 100 is composed of three layers of a base material, a hologram optical material, and a protective sheet, when the cut region is rectangular, the base material of the cut region is the same as above. At the time of peeling, partial peeling occurs between the hologram optical material and the protective sheet, and bubbles are caught in this peeling portion when the cut-out area is stuck.

  On the other hand, in the joining step, for example, the two optical members are joined by injecting an adhesive into the gap between the two optical members and curing the adhesive. Here, in FIG. 29, when the rectangular cut-out region is pasted on the optical surface of one optical member 201 to form an optical functional member 103 ′, and then an adhesive is injected between the two optical members. 5 schematically shows how the adhesive spreads.

  If the adhesive collides with the outer shape (short side) of the rectangular optical functional member 103 ′ while the adhesive flows through the gap between the two optical members, the flow of the adhesive stagnates in the vicinity of the short side. The agent stops flowing in a certain direction. In addition, the adhesive whose flow has stagnated in the vicinity of the short side collides with the adhesive flowing around the optical functional member 103 ′. At the time of the collision, surrounding air is entrained, and bubbles A are generated. . In the vicinity of the short side, the flow of the adhesive is stagnant, so that the generated bubbles A do not move in the vicinity of the short side and remain.

  Thus, when the cut-out area of the optical sheet 100 is rectangular or the optical functional member 103 ′ is rectangular, bubbles that lead to deterioration of permeability are generated in the lens assembly process. It is desirable to suppress the generation of various bubbles.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an optical lens capable of suppressing the generation of air bubbles in the lens assembly process and thereby suppressing the deterioration of permeability, and the optical lens. It is an object of the present invention to provide an image display device and a head mounted display, an optical sheet used for manufacturing the optical lens, and a method for manufacturing an optical lens using the optical sheet.

  An optical lens according to an aspect of the present invention includes a first optical member having a first optical surface, a second optical member having a second optical surface, and the first optical surface or the second optical surface. An optical lens having an optical function member formed on an optical surface and having an optical function, and a joining member that joins the first optical surface and the second optical surface via the optical function member. The optical functional member has a narrow width portion that becomes narrower as it approaches an end portion in a direction perpendicular to the width direction in plan view.

  In the optical lens, it is preferable that an angle formed by two sides defining the width of the narrow portion is 60 ° to 140 °.

  In the optical lens, it is preferable that two sides defining the width of the narrow portion are connected via a curved portion having a radius of curvature of 0.5 mm or more located at the end portion.

  The optical function member may have the narrow portion at both ends in a direction perpendicular to the width direction.

  The optical function member may be a hologram optical element produced by exposing a hologram photosensitive material.

  An image display apparatus according to another aspect of the present invention is an image display apparatus having a display element for displaying an image and an eyepiece optical system for guiding image light from the display element to an observer's pupil, The eyepiece optical system includes the optical lens described above.

  A head mounted display according to still another aspect of the present invention includes the above-described video display device and a support member that supports the video display device in front of an observer's eyes.

  An optical sheet according to still another aspect of the present invention is an optical sheet in which a plurality of layers containing a hologram photosensitive material are held on a resin sheet, and the optical sheet has an outer shape of a cut-out region of the plurality of layers. And a notch for separating the cut region from the resin sheet is included, and the cut region becomes narrower as it approaches an end in a direction perpendicular to the width direction in plan view. It has a narrow part.

  In the optical sheet, it is preferable that an angle formed by two sides defining the width of the narrow portion is 60 ° to 140 °.

  In the optical sheet, it is preferable that two sides defining the width of the narrow portion are connected via a curved portion having a radius of curvature of 0.5 mm or more located at the end portion.

  The cut region may have the narrow portion at both ends in a direction perpendicular to the width direction.

  The plurality of layers may include the hologram photosensitive material and a protective sheet from the resin sheet side.

  When the resin sheet is a first resin sheet, the plurality of layers may include an adhesive sheet, the hologram photosensitive material, and a second resin sheet from the first resin sheet side.

  An optical lens manufacturing method according to still another aspect of the present invention is an optical lens manufacturing method in which an optical lens is manufactured using the above-described optical sheet, the cutting out from the resin sheet of the optical sheet. A step of peeling the region starting from the end of the narrow portion, a step of sticking the peeled cut region to one optical surface of two optical members, and exposing the sticked cut region Then, the method includes a step of manufacturing a hologram optical element and a step of bonding the optical surfaces of the two optical members with a bonding member via the hologram optical element.

  An optical lens manufacturing method according to still another aspect of the present invention is an optical lens manufacturing method using the above optical sheet, wherein the hologram photosensitive material of the optical sheet is exposed to light. A step of producing a hologram optical element in the cut-out area, a step of peeling the cut-out area from the first resin sheet of the optical sheet, starting from the end of the narrow width part, and peeling The step of attaching the cut region to one optical surface of the two optical members via the adhesive sheet, and the respective optical surfaces of the two optical members with a bonding member through the attached cut region Joining.

  In the step of joining with the joining member, the joining member may be injected into a gap between the two optical members and cured.

  In the step of bonding with the bonding member, the bonding member is applied onto one optical surface of the two optical members, the two optical members are narrowed to a predetermined interval, and the bonding member is moved along the optical surface. After spreading, the joining member may be cured.

  The generation of bubbles can be suppressed in the assembly process of the optical lens, and this can suppress the deterioration of the transparency of the optical lens.

1 is a perspective view showing a schematic configuration of an optical lens according to an embodiment of the present invention. It is sectional drawing of the said optical lens. It is a top view which shows typically the shape of the optical function member which the said optical lens has. It is a top view of a part of the optical function member. It is sectional drawing which shows the schematic structure of the optical sheet used for manufacture of the said optical lens. It is a top view of the said optical sheet. It is a flowchart which shows the flow of the manufacturing process of the said optical lens. It is a perspective view which shows typically the mode at the time of peeling of the cutting area of the said optical sheet. It is explanatory drawing which shows typically the location where a stress is applied at the time of a peeling start in the said cut-out area | region. It is a perspective view which shows the state before joining of the two optical members which comprise the said optical lens. It is explanatory drawing which shows the injection | pouring location of the adhesive agent inject | poured into the clearance gap between the said two optical members. It is sectional drawing of the said optical lens at the time of injection | pouring of the said adhesive agent. It is explanatory drawing which shows typically a mode that the said adhesive agent inject | poured into the said space | gap spreads. It is a top view which shows typically a part of process of apply | coating a joining member to one optical surface of said two optical members, and joining said two optical members. It is a top view which shows the other shape of the said optical function member. It is a top view which shows the other shape of the cutting area of the said optical sheet. It is a top view which shows other shape of the said optical function member. It is a top view which shows other shape of the cutting-out area | region of the said optical sheet. It is a top view which shows other shape of the said optical function member. It is a top view which shows other shape of the cutting-out area | region of the said optical sheet. It is sectional drawing which shows the structure of another optical sheet. It is a top view of said other optical sheet. It is a flowchart which shows the flow of the other manufacturing process of the said optical lens. It is a top view of a head mount display (HMD) to which the above-mentioned optical lens is applied. It is a front view of the HMD. It is a bottom view of the HMD. It is a perspective view from the front side of the HMD. It is sectional drawing of the video display apparatus of the said HMD. It is sectional drawing which shows typically a mode that a base material is peeled in the conventional optical sheet. It is explanatory drawing which shows typically the location where stress is applied to the remaining cutting area at the time of peeling of the said base material. An explanation schematically showing how the adhesive spreads when the cut-out region is pasted on one optical surface of two optical members to form an optical functional member and an adhesive is injected between the two optical members. FIG.

  An embodiment of the present invention will be described below with reference to the drawings. In addition, in this specification, when a numerical range is described as ab, the value of the lower limit a and the upper limit b shall be included in the numerical range. The present invention is not limited to the following contents.

(Configuration of optical lens)
FIG. 1 is a perspective view illustrating a schematic configuration of the optical lens 1 of the present embodiment, and FIG. 2 is a cross-sectional view of the optical lens 1. In FIG. 2, a thick solid line indicates an optical path of video light when the optical lens 1 of the present embodiment is applied to a video display device 51 (see FIG. 26) described later. The optical lens 1 is configured by joining an optical member 2 (first optical member) and an optical member 3 (second optical member) with a joining member 4.

  The optical members 2 and 3 are prisms made of transparent resin or glass. The optical member 2 has a surface 2a as a first optical surface. The optical member 3 has a surface 3a as a second optical surface. The surface 2a and the surface 3a are in a positional relationship facing each other when the optical members 2 and 3 are joined. For example, the surface 2a and the surface 3a are each formed by a curved surface (convex surface or concave surface) having a curvature only in one direction, but may be formed by a flat surface. The joining member 4 is an adhesive that adheres two members, and is made of, for example, a photo-curing resin that is cured by irradiation of ultraviolet rays or a thermosetting resin.

  An optical functional member 5 having an optical function is formed on the surface 2a. As the optical functional member 5, for example, a volume phase type hologram optical element 5a that diffracts and reflects only light in a predetermined wavelength region of incident light can be considered. Such a hologram optical element 5a is, for example, an optical sheet (hologram sheet) in which a hologram photosensitive material is held on a resin sheet. A region to be attached to the surface 2a is cut out in a predetermined shape, and the cut out region (cutout region) is cut out. It is manufactured by peeling off the resin sheet and attaching it to the surface 2a, and exposing the attached hologram photosensitive material in the cut-out area. By thus forming the hologram optical element 5a on the surface 2a, an optical function (diffraction reflection function) can be imparted to the surface 2a. In addition, the optical function member 5 (hologram optical element 5a) may be formed on the surface 3a to give the optical function to the surface 3a.

(Planar shape of optical functional member)
FIG. 3 is a plan view schematically showing the shape of the optical function member 5, and FIG. 4 is a plan view of a part of the optical function member 5 in FIG. The optical function member 5 has a uniform width portion 11 and a narrow width portion 12. In the present embodiment, the narrow width portions 12 are provided on both sides so as to sandwich the equal width portion 11 therebetween.

  For convenience of explanation below, in plan view, the width direction of the optical function member 5 is the D1 direction, and the direction perpendicular to the width direction (D1 direction) is the D2 direction. In addition, when the optical function member 5 is long in the D2 direction, the D2 direction can also be referred to as the long direction. Unless otherwise specified, the shape of the optical functional member 5 described below refers to a shape in a plan view (a shape in a plane including the D1 direction and the D2 direction).

  The equal width portion 11 is a portion where the width in the D1 direction is uniform in the D2 direction, and is a portion that exhibits the optical function of the optical function member 5 (diffractive reflection function in the case of the hologram optical element 5a). As shown in FIG. 3, the equal width portion 11 is curved in a plane including the D1 direction and the D2 direction according to the curved shape of the surface 2 a of the optical member 2. However, the width in the D1 direction is uniform at W0 at any position in the D2 direction. When the surface 2a of the optical member 2 is a flat surface, the equal width portion 11 may be a quadrangular shape (for example, a rectangular shape) that does not curve in a plane including the D1 direction and the D2 direction (see FIG. 15).

  Each narrow width portion 12 is provided continuously to the equal width portion 11 on both sides in the D2 direction with respect to the equal width portion 11. Each narrow width portion 12 is formed in a shape in which the width in the D1 direction becomes narrower as it approaches the end in the D2 direction. For example, when the widths of one narrow width portion 12 at different positions in the D2 direction are W1 and W2 from the equal width portion 11 side, W2 <W1. Then, at the connection portion between the narrow width portion 12 and the equal width portion 11, the width of the narrow width portion 12 matches the width W 0 of the equal width portion 11. In addition, each narrow width portion 12 has a shape and positional relationship that is line-symmetric with respect to an axis that passes through the center in the D2 direction of the equal width portion 11 and is parallel to the D1 direction.

  The outer shape (planar shape) of each narrow portion 12 is defined by two sides 12a and 12b and a curved portion 12c that connects these sides 12a and 12b. The two sides 12a and 12b are sides that define the width of the narrow portion 12, and the angle formed by the two sides 12a and 12b is set to 60 ° to 140 °. The curved portion 12c is located at the end in the D2 direction and connects the two sides 12a and 12b. The curved portion 12c has a radius of curvature of 0.5 mm or more, and is formed in a shape that is convex toward the outside in the D2 direction (the side opposite to the uniform width portion 11).

  Such an optical function member 5 is produced using the optical sheet shown below. Hereinafter, this optical sheet will be described.

(About optical sheets)
FIG. 5 is a cross-sectional view showing a schematic configuration of the optical sheet 20 of the present embodiment. The optical sheet 20 is configured by holding a plurality of layers on a resin sheet 21. The plurality of layers include the hologram photosensitive material 22 and the protective sheet 23 from the resin sheet 21 side.

  The resin sheet 21 is a base material for manufacturing the optical functional member 5 and is formed of a thin film sheet made of a resin such as PET (polyethylene terephthalate). The hologram photosensitive material 22 is a photosensitive material for producing the hologram optical element 5a, and is made of, for example, a photopolymer. The hologram photosensitive material 22 is gel-like and has adhesiveness. The protective sheet 23 is a protective member that covers the hologram photosensitive material 22 and is formed of a thin film sheet made of a resin such as TAC (triacetyl cellulose). Predetermined regions (cut-out regions 20R described later) of the second and third hologram photosensitive materials 22 and the protective sheet 23 counted from the resin sheet 21 side are used for manufacturing the optical function member 5 described above.

  The optical sheet 20 has a cut 20L from the protective sheet 23 side to the middle of the resin sheet 21. In other words, the resin sheet 21 is not half-cut in the thickness direction but half-cut. The cut 20L defines the outer shape of the cut region 20R cut from the optical sheet 20, and is formed to peel the cut region 20R from the resin sheet 21 in a predetermined shape. The cut area 20R includes a cut area 22R of the hologram photosensitive material 22 and a cut area 23R of the protective sheet 23.

FIG. 6 is a plan view of the optical sheet 20. The cutout region 20R of the optical sheet 20 has a uniform width portion 20R ₁ and a narrow width portion 20R ₂ adjacent thereto. In the present embodiment, the narrow width portion 20R ₂ is provided on both sides of the narrow width portion 20R _{1 so} as to sandwich the equal width portion 20R ₁ therebetween. The cutout region 20R corresponds to the optical function member 5 described above, and the planar shape of the cutout region 20R is the same as the planar shape of the optical function member 5. Further, the equal width portion 20R ₁ and the narrow width portion 20R ₂ of the cutout region 20R correspond to the equal width portion 11 and the narrow width portion 12 of the optical function member 5, respectively. The planar shapes of the equal width portion 20R ₁ and the narrow width portion 20R ₂ are the same as the planar shapes of the equal width portion 11 and the narrow width portion 12.

Hereinafter, the shapes of the equal width portion 20R ₁ and the narrow width portion 12 of the cutout region 20R will be described in a confirming manner. 6 also uses the same definition as in FIG. 3 for each in-plane direction. That is, in the plan view of the optical sheet 20, the width direction of the cutout region 20R is defined as the D1 direction, and the direction perpendicular to the width direction (D1 direction) is defined as the D2 direction.

The equal width portion 20R ₁ is a portion where the width in the D1 direction is uniform in the D2 direction. In FIG. 6, the width in the D1 direction of the equal width portion 20R ₁ is uniform at W0 at any position in the D2 direction. Each narrow portion 20R ₂ is on both sides of the D2 direction relative to an equal width portion 20R _1, are respectively provided continuously with an equal width portion 20R _1, none, D1 direction toward the end of the D2 direction It is formed in a shape in which the width of is narrow. At the connection location with the equal width portion 20R ₁ , the width of each narrow width portion 20R ₂ matches the width W0 of the equal width portion 20R ₁ . Each narrow-width portion 20R ₂ has a shape and positional relationship that is line-symmetric with respect to an axis that passes through the center in the D2 direction of the equal-width portion 20R ₁ and is parallel to the D1 direction.

The outer shape (planar shape) of each narrow portion 20R ₂ is defined by two sides 20a and 20b and a curved portion 20c that connects these sides 20a and 20b. Two sides 20a · 20b are side defining the width of the narrow portion 20R _2, the angle of the two sides 20a · 20b is set to 60 ° to 140 °. The curved portion 20c is located at the end in the D2 direction and connects the two sides 12a and 12b. Curve portion 20c is a curvature radius of 0.5mm or more, and is formed in a shape which is convex toward the (opposite side of the equal width portion 20R ₁₎ D2 direction outward.

(About optical lens manufacturing method)
Next, a method for manufacturing the optical lens 1 using the optical sheet 20 will be described with reference to FIG. FIG. 7 is a flowchart showing the flow of the manufacturing process of the optical lens 1.

  First, as shown in FIG. 6, the optical sheet 20 is provided with a cut 20L that forms the outer shape of the cut region 20R (S1; cutting step). That is, a cutting tool is inserted from the side of the protective sheet 23 of the third layer and the cutting (cutting) of the cutting tool is stopped at a half of the thickness of the resin sheet 21 of the first layer, so that the optical sheet 20 is cut 20L.

Subsequently, from the first resin sheet 21 of the optical sheet 20, the second and third cutout regions 20R (the cutout region 22R and the cutout region 23R) are peeled along the cut 20L (S2). A peeling step). More specifically, as shown in FIG. 8, the optical sheet 20 is conveyed in the D2 direction on the peeling plate 31 so that the resin sheet 21 is on the peeling plate 31 side, and a cutout region 20R of the optical sheet 20 is obtained. The other three layers are bent at an acute angle so as to pass between the roller 32 and the peeling plate 31. Thus, starting from the end of the D2 direction in the narrow portion 20R ₂ (curved portion 20c side), cut region 20R is peeled.

At this time, as shown in FIG. 9, the stress applied to the cut region 20R at the start peeling is concentrated in approximately one point at the end of D2 direction in the narrow portion 20R _2. Note that (as compared to the stressed configuration for peeling the entire short side) as compared with the case where the shape of the cut-out area is a rectangular shape, the end portion of the narrow portion 20R ₂ to about 5-7 times the stress It is known from simulation that it can concentrate on

  Since the stress at the start of peeling is concentrated on the end portion, when the peeling starts, the second layer (hologram photosensitive material 22) of the cutout region 20R is pulled toward the first layer (resin sheet 21). There is almost one point (local), not the entire direction. For this reason, the second layer and the third layer are less likely to be peeled off at the start of peeling, compared to a configuration in which the shape of the cut-out region is rectangular and stress is applied to the entire short side during peeling. In this way, the partial area peeling between the second layer and the third layer is suppressed, and the peeling of the cut region 20R gradually proceeds in the direction D2 from the end portion, and the peeling of the entire surface is completed. The cut-out area 20R thus peeled off is conveyed while adsorbing the protective sheet 23 side by, for example, an adsorbing member (not shown).

  Next, the separated cut-out region 20R is conveyed to the attachment position of one optical surface (for example, the surface 2a) of the two optical members 2 and 3 while being adsorbed and held by the adsorbing member, and is pressed by a roller or the like. Thus, the cutout region 20R is pasted on the optical surface from the hologram photosensitive material 22 side (S3; pasting step). Since the hologram photosensitive material 22 has adhesiveness, the cutout region 20R is attached to the optical surface by the adhesiveness.

  Then, the cutout region 20R attached to the optical surface is exposed with two light beams to form interference fringes on the hologram photosensitive material 22, and the hologram optical element 5a as the optical functional member 5 is produced (S4; HOE creation) Process). Thereafter, the optical surfaces of the two optical members 2 and 3 are joined by the joining member 4 (for example, an adhesive) via the hologram optical element 5a (S5; joining step).

  The said joining process is demonstrated in detail. FIG. 10 is a perspective view showing a state before the two optical members 2 and 3 are joined, and FIG. 11 shows an injection position of the adhesive into the gap between the optical surfaces of the two optical members 2 and 3. Yes.

  First, the optical members 2 and 3 are fixed with a certain gap. The gap amount at this time is set to a thickness (for example, 10 to 100 μm) at which the optical functional member 5 is not deformed by the curing shrinkage of the adhesive injected into the gap.

  Next, an adhesive is injected into the gap. At this time, in order to prevent the adhesive from leaking to the outside through the gap, as shown in FIG. 12, resin sheets 35 and 36 having high water repellency are arranged so as to sandwich the optical members 2 and 3, and further outside thereof. For example, fixing members 37 and 38 having flatness such as glass are disposed, and the optical members 2 and 3 are sandwiched therebetween. The resin sheets 35 and 36 and the fixing members 37 and 38 are not arranged on the side where the adhesive is injected and discharged from the gap.

  In addition, in order to absorb the level | step difference (error of prism thickness) of the optical member 2 * 3 and to improve sealing performance, as shown in FIG. 12, the resin sheet 36 and the fixing member 38 may be used as necessary. An elastic member 39 such as rubber may be disposed between them. One flat plate (for example, the fixing member 37) may be a transparent material. Thereby, when an ultraviolet curable adhesive is used as the adhesive, the adhesive can be cured by irradiating the adhesive with ultraviolet rays for curing via the flat plate.

  Next, an adhesive is injected into the gap between the optical members 2 and 3 from the narrow width portion 12 side of the optical function member 5 (hologram optical element 5a) and cured. More specifically, a member having a high sealing property and having a small diameter hole in the center is pressed to the side of the gap between the optical members 2 and 3, and an adhesive is injected into the gap from the hole. Then, when the adhesive spreads over the entire gap, the injection of the adhesive is stopped. Thereafter, the adhesive is cured by ultraviolet irradiation. Thereby, the optical members 2 and 3 are joined by the adhesive. The excess adhesive may be discharged and removed from the side opposite to the adhesive injection side with respect to the gap between the optical members 2 and 3.

As described above, the optical functional member 5 constituting the optical lens 1 of the present embodiment has a narrow width that becomes narrower as it approaches the end in the direction (D2 direction) perpendicular to the width direction (D1 direction) in plan view. It has a width portion 12. Such an optical function member 5 can be produced by using the optical sheet 20 described above. That is, the optical sheet 20 includes an incision 20 </ b> L for forming the outer shape of the cutout region 20 </ b> R and for peeling the cutout region 20 </ b> R from the resin sheet 21. The above segment region 20R is closer to the end portion in the direction perpendicular to the width direction (D1 direction) in a plan view (D2 direction), and has a narrow portion 20R ₂ in which the width is narrowed. Thereby, the following effects can be acquired.

By segment region 20R has a narrow portion 20R _2, upon the release of the cut region 20R from the optical sheet 20, as described above, the stress at the start peeling of the narrow portion 20R ₂ D2 It is possible to prevent the hologram photosensitive material 22 and the protective sheet 23 constituting the plurality of layers of the cutout region 20R from being partially separated by being concentrated at the end in the direction. Thereby, it can reduce that a bubble enters between the hologram photosensitive material 22 and the protective sheet 23 at the time of pasting to the optical surface (for example, surface 2a) of the cut-out area | region 20R which peeled. Further, by concentrating the stress at the start of peeling on the end portion, the cutout region 20R can be peeled smoothly and the peelability is improved.

In addition, the cut region 20R has a narrow portion 20R ₂ , and the optical function member 5 produced using the cut region 20R has the narrow portion 12, thereby allowing an adhesive in the joining process. It is also possible to reduce the generation of bubbles at the time of injection. That is, as shown in FIG. 13, even when the injected adhesive hits the end of the narrow portion 12, it is smoothly separated in the width direction and flows along the sides 12 a and 12 b of the narrow portion 12. For this reason, it can reduce that the adhesives collide violently by the vicinity of the edge | side 12a * 12b, and its circumference | surroundings, and entrap surrounding air can be reduced, As a result, generation | occurrence | production of a bubble can be reduced. In addition, since the adhesive in the vicinity of the sides 12a and 12b flows along the sides 12a and 12b, even if the bubbles A are generated for some reason in the vicinity of the sides 12a and 12b, the bubbles A flow in the adhesive. Is carried downstream and discharged with unnecessary adhesive. For this reason, the bubble A does not stay in the gap between the optical members 2 and 3. Even if dust is mixed in the gap between the optical members 2 and 3, it can be discharged by the flow of the adhesive as described above.

  As described above, in the assembly process (including the pasting process and the joining process) of the optical lens 1, it is possible to suppress the generation of air bubbles and avoid the introduction of dust, so that it is possible to suppress the deterioration of the permeability of the optical lens 1. . As a result, the optical lens 1 as an information output device having high see-through property can be manufactured.

The angle formed by the two sides 12a and 12b that define the width of the narrow portion 12 is 60 ° to 140 °. This configuration can be easily realized by manufacturing an optical functional member 5 by using an optical sheet 20 which sets the angle between two sides 20a · 20b of the narrow portion 20R ₂ to 60 ° to 140 °.

  By setting the angle to 140 ° or less, the end of the narrow portion 12 in the D2 direction approaches sharply, so that the adhesive that collides with the end of the narrow portion 12 during injection is reliably separated in the D1 direction. In addition, the adhesive can be flowed along the sides 12a and 12b without surrounding air. As a result, it is possible to reliably reduce the generation and residual of bubbles during bonding. Further, by setting the angle to 60 ° or more, the length and area of the equal width portion 11 in the D2 direction can be increased, and a large area (effective area) where the optical function can be exhibited can be secured (optical function). When the length of the member 5 in the D2 direction is constant, if the angle is less than 60 °, the narrow width portion 12 becomes longer in the D2 direction. Therefore, the length and area of the equal width portion 11 in the D2 direction are small. Become).

Further, the two sides 12a and 12b that define the width of the narrow width portion 12 are connected via a curved portion 12c having a radius of curvature of 0.5 mm or more located at an end portion in the D2 direction. This configuration, in the optical sheet 20, the two sides 20a · 20b of the narrow portion 20R _2, linked via a curvature radius 0.5mm or more curved portions 20c located at the end of the D2 direction, the optical sheet 20 This can be easily realized by producing the optical functional member 5 using

  Thus, by giving curvature to the end portion of the narrow width portion 12 in the D2 direction, the strength of the end portion can be ensured, and bending or breakage of the end portion in the lens assembling process can be reduced. it can.

Moreover, in this embodiment, the optical function member 5 has the narrow part 12 in the both ends of D2 direction. This configuration can be easily realized by manufacturing an optical functional member 5 by using an optical sheet 20 cut region 20R has a narrow portion 20R ₂ at both ends of the D2 direction.

  Since the optical functional member 5 has the narrow portions 12 at both ends, in the joining process, as shown in FIG. 13, the adhesive is injected from the one narrow portion 12 side, and the other narrow width portion. The adhesive can be discharged from the part 12 side. At this time, even on the adhesive discharge side, the width of the narrow portion 12 in the D1 direction gradually becomes narrower toward the end portion in the D2 direction (on the opposite side to the injection side), so that the adhesive becomes the sides 12a and 12b. It flows smoothly along and is discharged, and the flow of adhesive does not stagnate. Further, even if bubbles are generated for some reason, the bubbles can be discharged in the flow of the adhesive. Therefore, it is possible to reliably reduce bubbles remaining in the gap between the optical members 2 and 3.

  The optical function member 5 is a hologram optical element 5a produced by exposing the hologram photosensitive material 22. The hologram optical element 5a has wavelength selectivity, and has an optical function of diffracting and reflecting only light in a predetermined wavelength region of incident light and transmitting the remaining light. Therefore, the optical lens 1 of the present embodiment can be applied to a transmissive wearable display that allows an image and the external world to be observed simultaneously. That is, the hologram optical element 5a can diffract and reflect the image light and guide it to the observer's pupil, while allowing the external light to pass therethrough, so that the optical lens 1 suitable for a transmissive wearable display can be realized. it can.

  The plurality of layers on the resin sheet 21 of the optical sheet 20 include a hologram photosensitive material 22 and a protective sheet 23 from the resin sheet 21 side, and the optical sheet 20 has a three-layer structure as a whole. In the optical sheet 20 having such a three-layer structure, by defining the outer shape of the cutout region 20R as described above, when the cutout region 20R is peeled, a plurality of layers (hologram photosensitive material 22 and protective sheet 23 and (Between), partial peeling occurs, and it is possible to reduce a situation in which bubbles are caught in the peeling part at the time of sticking.

Moreover, the manufacturing method of the optical lens 1 includes the step (S2) of peeling the cut region 20R from the resin sheet 21 of the optical sheet 20 with the end portion in the D2 direction of the narrow width portion 20R ₂ as a starting point, and the peeled cut A step (S3) of attaching the region 20R to one optical surface (for example, the surface 2a) of the two optical members 2 and 3, and a step of exposing the attached cutout region 20R to produce the hologram optical element 5a. (S4) and a step (S5) of joining the optical surfaces of the two optical members 2 and 3 with the joining member 4 via the hologram optical element 5a. By producing the optical lens 1 through such processes, the generation of bubbles in the lens assembly process can be suppressed.

  Further, in the joining step of S5, the joining member 4 is injected into the gap between the two optical members 2 and 3 and cured. Thus, in the case where the two optical members 2 and 3 are joined by injection and curing of the joining member 4, the effect of the present embodiment that suppresses the generation of bubbles can be obtained.

  By the way, the joining in the joining step of S5 is not limited to the joining by the injection and curing of the joining member 4 into the gap. For example, as shown in FIG. 14, the joining member 4 is applied to one optical surface (for example, the surface 2a) of the two optical members 2 and 3, and the two optical members 2 and 3 are separated at a predetermined interval (at the time of adhesive injection). The bonding member 4 may be hardened after the bonding member 4 is pushed and spread along the optical surface.

  For example, when the bonding member 4 is applied to the outer surface of the optical function member 5 near the end in the D2 direction of one narrow width portion 12 of the optical function member 5, the bonding member 4 is spaced from the optical members 2 and 3. By narrowing, it spreads wet along the optical surface. Even in this case, the joining member 4 flows along the sides 12a and 12b of one narrow width portion 12 without colliding with the surrounding joining members 4 (without entraining air) as in the case of FIG. Therefore, it is possible to reduce the generation of bubbles. Further, in the vicinity of the other narrow width portion 12, the width of the narrow width portion 12 is gradually narrowed toward the end portion, so that the joining member 4 is smoothly spread toward the discharge side. For this reason, even if bubbles are generated for some reason in the bonding process, the bubbles can be discharged out of the lens by being put on the flow of the bonding member 4. Therefore, as described above, even when the joining member 4 is applied to the optical surface and the optical members 2 and 3 are joined, it is possible to reduce bubbles remaining between the optical members 2 and 3 in the joining process. .

  The optical sheet 20 may have a configuration in which three layers of a resin sheet, a bonding member, and a reflecting member are laminated in this order. The reflecting member can be formed, for example, by vapor deposition of a metal thin film (including a multilayer film). In this case, the optical function member 5 can function as a total reflection mirror or a half mirror. Even with such a configuration of the optical sheet 20, the generation of bubbles in the lens assembly process can be reduced by setting the shape of the cutout region 20R as in the present embodiment.

(Optical function members and other shapes of the cutout area)
15 and 16 are plan views showing other shapes of the optical function member 5 and the cutout region 20R. As shown in FIG. 15, the equal width portion 11 of the optical function member 5 may have a rectangular shape in which the long side direction is the D2 direction in plan view. Further, as shown in FIG. 16, the equal width portion 20R ₁ of the cutout region 20R of the optical sheet 20 may also have a rectangular shape in which the long side direction is the D2 direction in plan view.

  17 and 18 are plan views showing still other shapes of the optical function member 5 and the cutout region 20R. As shown in FIG. 17, the outer shape of the narrow width portion 12 of the optical function member 5 may be defined by the first curved portion 12d, the second curved portion 12e, and the third curved portion 12f in plan view. Good. The first curved portion 12d and the second curved portion 12e are concave shapes facing the D1 direction which is the width direction and recessed inside the optical function member 5. The third curved portion 12f is a curved portion that connects the first curved portion 12d and the second curved portion 12e at the position of the end in the D2 direction, and has a convex shape that bulges outside the optical function member 5. It has become.

As shown in FIG. 18, the narrow outer width portion 20R ₂ of segment region 20R of the optical sheet 20 is a plan view, the first curved portion 20d, the second curved portion 20e and the third curved portion 20f It may be specified. The first curved portion 20d and the second curved portion 20e have a concave shape facing the direction D1, which is the width direction, and recessed inside the cutout region 20R. The third curved portion 20f is a curved portion that connects the first curved portion 20d and the second curved portion 20e at the position of the end in the D2 direction, and has a convex shape that swells outside the cutout region 20R. It has become.

  19 and 20 are plan views showing still other shapes of the optical function member 5 and the cutout region 20R. As shown in FIG. 19, the outer shape of the narrow portion 12 of the optical function member 5 may be defined by the first curved portion 12g, the second curved portion 12h, and the third curved portion 12i in plan view. Good. The first curved portion 12g and the second curved portion 12h have a convex shape that faces the direction D1, which is the width direction, and bulges outside the optical function member 5. The third curved portion 12i is a curved portion that connects the first curved portion 12g and the second curved portion 12h at the position of the end in the D2 direction, and has a convex shape that bulges outside the optical function member 5. It has become.

As shown in FIG. 20, the narrow outer width portion 20R ₂ of segment region 20R of the optical sheet 20 is a plan view, the first curved portion 20g, the second curved portion 20h and the third curved portion 20i It may be specified. The first curved portion 20g and the second curved portion 20h have a convex shape that faces the width direction D1 and bulges outside the cutout region 20R. The third curved portion 20i is a curved portion that connects the first curved portion 20g and the second curved portion 20h at the position of the end in the D2 direction, and has a convex shape that swells outside the cutout region 20R. It has become.

The outer shape of the optical functional member 5 and the segment region 20R is, even for the shape shown in FIGS. 15 to 20, the narrow portion 20R ₂ of the narrow portion 12 and a segment region 20R of the optical functional member 5, plan Since the width becomes narrower as it approaches the end portion in the D2 direction, the generation of bubbles in the lens assembly process can be reduced, and the permeability deterioration of the optical lens 1 can be suppressed.

In the above, the direction D2 of the end portion of the narrow portion 12 of the optical functional member 5, and the end of the D2 direction narrow portion 20R ₂ of segment region 20R is, the case where the center position in the width direction Although explained, it may be shifted in the D1 direction from the center in the width direction.

  In the above description, the number of cutout areas 20R formed on the optical sheet 20 is one. However, the optical sheet 20 is formed in a long shape, and a plurality of cutout areas 20R are provided at predetermined intervals in the long direction. They may be formed side by side.

(Configuration of other optical sheets)
FIG. 21 is a cross-sectional view showing a configuration of another optical sheet 40 that can be used for manufacturing the optical functional member 5. The optical sheet 40 is configured by laminating an optical adhesive sheet 42, also called OCA (Optical Clear Adhesive), a gel-like hologram photosensitive material 43, and a second resin sheet 44 on a first resin sheet 41. ing.

  The optical sheet 40 has a cut 40 </ b> L from the second resin sheet 44 side to the middle of the first resin sheet 41. That is, the resin sheet 41 is not half-cut in the thickness direction but half-cut. The cut 40L defines the outer shape of the cut region 40R cut from the optical sheet 40, and is formed to peel the cut region 40R from the resin sheet 41 in a predetermined shape. The cut region 40R includes a cut region 42R of the optical adhesive sheet 42, a cut region 43R of the hologram photosensitive material 43, and a cut region 44R of the second resin sheet 44.

FIG. 22 is a plan view of the optical sheet 40. The shape of the cutout region 40R of the optical sheet 40 in plan view is the same as the shape of the cutout region 20R of the optical sheet 20 described above. In other words, cut region 40R of the optical sheet 40 includes a constant width portion 40R _1, and a narrow portion 40R _2. The cutout region 40R corresponds to the optical function member 5 described above, and the planar shape of the cutout region 40R is the same as the planar shape of the optical function member 5. The equal width portion 40R ₁ and the narrow width portion 40R ₂ of the cutout region 40R correspond to the equal width portion 11 and the narrow width portion 12 of the optical function member 5, respectively, and the equal width portion 40R ₁ and the narrow width portion 40R _2. The planar shape is the same as the planar shape of the equal width portion 11 and the narrow width portion 12.

The equal width portion 40R ₁ is a portion where the width in the D1 direction is uniform in the D2 direction. Narrow portion 40R ₂ is on both sides of the D2 direction relative to an equal width portion 40R _1, is provided continuously with an equal width portion 40R _1. Each narrow portion 40R ₂ is formed in the D1 direction width is narrowed shape toward the end of the D2 direction. At the connection location with the equal width portion 40R ₁ , the width of each narrow width portion 40R ₂ matches the width of the equal width portion 20R ₁ . Each narrow width portion 40R ₂ has a shape and positional relationship that is line-symmetric with respect to an axis that passes through the center in the D2 direction of the equal width portion 40R ₁ and is parallel to the D1 direction.

The shape of the narrow portion 40R ₂ is defined with two edges 40a · 40b, by a curved portion 40c that these edges 40a · 40b which is linked with the position of the direction D2 of the end portion. The angle formed by the two sides 40a and 40b is set to 60 ° to 140 °. Curve portion 40c is a curvature radius of 0.5mm or more, and is formed in a shape which is convex toward the (opposite side of the equal width portion 40R ₁₎ D2 direction outward.

  Next, a method for manufacturing the optical lens 1 using the optical sheet 40 will be described with reference to FIG. FIG. 23 is a flowchart showing the flow of another manufacturing process of the optical lens 1.

  First, the notch 40L which forms the external shape of the cutting area 40R is put into the optical sheet 40 (S11; cutting step). That is, the cutting tool is inserted from the second resin sheet 44 side of the fourth layer and cut into the optical sheet 40 by stopping the cutting (cutting) of the cutting tool at half the thickness of the first resin sheet 41 of the first layer. Add 40L.

Next, the hologram photosensitive material 43 of the optical sheet 40 is exposed to produce the hologram optical element 5 in the cutout region 40R (S12; HOE creation step). Then, the cut region 40R where the hologram optical element 5 is formed is peeled from the first resin sheet 41 of the optical sheet 40 along the cut 40L (S13; peeling step). In this case, the narrow width portion 40R ₂ end of segment region 40R (the curved portion 40c side) as a starting point, separating the cut region 40R from the first resin sheet 41.

  Subsequently, the cut region 40R peeled off in S13 is pasted on one optical surface (for example, the surface 2a) of the two optical members 2 and 3 via the optical adhesive sheet 42 (S14; pasting step). Thereafter, the optical surfaces of the two optical members 2 and 3 are joined by the joining member 4 via the cutout region 40R (S15; joining step).

  Thus, the multiple layers on the first resin sheet 41 of the optical sheet 40 include the optical adhesive sheet 42, the hologram photosensitive material 43, and the second resin sheet from the first resin sheet 41 side. The optical sheet 40 has a four-layer structure as a whole. Even when the optical sheet 40 having such a four-layer structure is used, by defining the outer shape of the cutout area 40R in the same manner as the cutout area 20R of the optical sheet 20, a plurality of cutout areas 40R can be separated at the time of peeling. Partial peeling between layers (for example, between the optical adhesive sheet 42 and the hologram photosensitive material 43) can be suppressed. As a result, it is possible to reduce a situation in which bubbles are involved between the plurality of layers when the peeled cut region 40R is attached to the optical surface.

  Moreover, by producing the optical lens 1 through the above-described steps S11 to S15, it is possible to suppress the generation of bubbles in the lens assembly step (including the pasting step and the joining step).

(Application examples of optical lenses)
Next, an application example of the optical lens 1 of the present embodiment will be described. The optical lens 1 described above can be applied to, for example, a head mounted display (HMD) that allows an observer to observe an image (virtual image) and to observe the outside world through a see-through. Hereinafter, this HMD will be described.

  24A, 24B, and 24C are a top view, a front view, and a bottom view of the HMD 50 of the present embodiment, and FIG. 25 is a perspective view from the front side of the HMD 50. In addition, in FIG. 24A etc., each direction of the orthogonal 3 axis | shaft XYZ is shown as needed. The directions of XYZ correspond to the observer's eye width direction (left-right direction), the front-rear direction, and the up-down direction, respectively.

  The HMD 50 includes a video display device 51, a frame 52, a lens 53, a nose pad 54, and a position adjustment mechanism 55. The optical lens 1 of the present embodiment described above is applied to the observation optical system 70 (see FIG. 26) of the video display device 51. Details of the video display device 51 will be described later.

  The frame 52 corresponds to a frame of glasses, and is a support member that is mounted on the observer's head and supports the video display device 51. The frame 52 includes temples that come into contact with the left and right temporal regions of the observer.

  The lens 53 includes a right-eye lens 53 </ b> R and a left-eye lens 53 </ b> L disposed in front of the right and left eyes of the observer. The right-eye lens 53R and the left-eye lens 53L are connected to the position adjustment mechanism 55 via the right connection portion 56R and the left connection portion 56L. The right-eye lens 53R and the left-eye lens 53L may be lenses for correcting vision, or may be simple dummy lenses that do not correct vision.

  The nose pad 54 includes a right nose pad 54R and a left nose pad 54L that come into contact with the nose of the observer. The right nose pad 54R and the left nose pad 54L are connected to the position adjusting mechanism 55 via the right connecting part 57R and the left connecting part 57L.

  The position adjustment mechanism 55 moves the nose pad 54 relative to the frame 52 in the vertical direction perpendicular to the viewer's eye width direction, thereby moving the vertical position of the video display device 51 supported by the frame 52. It is a mechanism that adjusts. Note that the lens 53 and the nose pad 54 may be directly fixed to the frame 52 without providing the position adjusting mechanism 55.

  FIG. 26 is a cross-sectional view of the video display device 51. The video display device 51 is a unit for allowing an observer to observe a virtual image, and includes an image generation unit 60 that generates an image and an observation optical system 70. The image generation unit 60 includes a light source 61, a unidirectional diffuser plate 62, a condenser lens 63, and a display element 64 in a housing 51a (see FIG. 24A and the like).

  The light source 61 illuminates the display element 64. For example, 462 ± 12 nm (B light), 525 ± 17 nm (G light), and 635 ± 11 nm (R) at a peak wavelength of light intensity and a wavelength width of half value of light intensity. It is composed of RGB-integrated LEDs that emit light in three wavelength bands. The unidirectional diffuser 62 is a diffuser that diffuses incident light in the X direction but does not diffuse in a direction perpendicular to the X direction. The condensing lens 63 is an optical system that condenses incident light in the YZ plane. The display element 64 modulates the light emitted from the light source 61 according to image data and displays an image. The display element 64 is a transmissive liquid crystal display element (LCD) having pixels in a matrix in which light is transmitted. ). The display element 64 may be a reflective display element. Power supply to the light source 61 and the display element 64 and transmission of image data to the display element 64 are performed via a cable (not shown).

  The observation optical system 70 includes the optical lens 1 described above, and includes an optical member 2 as an eyepiece prism, an optical member 3 as a deflection prism, and an optical function member 5. The optical function member 5 is formed on the surface 2 a of the optical member 2. The optical members 2 and 3 are joined by a joining member 4 (see FIG. 2).

  For example, when the observation optical system 70 is configured without joining the optical member 3 to the optical member 2, light from the outside (external light) is refracted when passing through the lower surface 2 a of the optical member 2. The external image observed through the optical member 2 is distorted. However, the optical member 3 can be canceled by the optical member 3 by joining the optical member 3 to the optical member 2 to form an integral substantially parallel flat plate. As a result, it is possible to prevent distortion in the external image observed through the see-through.

  The optical function member 5 is formed of, for example, a hologram optical element 5a. The hologram optical element is a volume phase reflection type hologram that diffracts and reflects image light (wavelength light corresponding to the three primary colors) emitted from the display element 64 and guides it to the optical pupil P. For example, the hologram optical element has diffraction efficiency. It is fabricated to diffract (reflect) light in three wavelength ranges of 465 ± 5 nm (B light), 521 ± 5 nm (G light), and 634 ± 5 nm (R light) with a peak wavelength and a half width of diffraction efficiency. ing.

  The reflection type hologram optical element has high wavelength selectivity, and only diffracts and reflects light having a wavelength in the above-mentioned wavelength range (near the exposure wavelength). Therefore, external light including wavelengths other than the wavelength to be diffracted and reflected is a hologram. The light is transmitted through the optical element, and a high external light transmittance can be realized.

  In the above configuration, each RGB light emitted from the light source 61 is diffused only in the X direction by the unidirectional diffusion plate 62, collected by the condenser lens 63, and then incident on the display element 64. In the display element 64, the incident light is modulated according to the image data, and enters the observation optical system 70 as image light.

  In the observation optical system 70, the image light from the display element 64 enters the optical member 2 through the incident surface 2b. The image light is totally reflected at least once on the surfaces 2c and 2d facing each other, guided through the inside, incident on the optical functional member 5 on the surface 2a, diffracted and reflected there, and then optically transmitted through the surface 2c. Head in the direction of pupil P. Therefore, when the observer's pupil is aligned with the position of the optical pupil P, the observer can observe an enlarged virtual image of the image displayed on the display element 64 forward.

  On the other hand, since the optical members 2 and 3 and the optical function member 5 transmit almost all of the external light, the observer can observe the external image with see-through. Therefore, the virtual image of the image displayed on the display element 64 is observed while overlapping with a part of the external image.

  In the HMD 50 described above, the observation optical system 70 (optical lens 1) of the image display device 51 is configured separately from the lens 53. However, the optical lens 1 is formed in the shape of the lens 53 and used as the lens 53. It is also possible. That is, the observation optical system 70 can be integrated with the lens 53. The above-described HMD 50 is a type that observes a video (virtual image) with one eye. However, the video display device 51 is arranged in front of both eyes so that an observer can observe the video (virtual image) with both eyes. Is also possible.

  The present invention can be used for manufacturing an optical lens applied to an observation optical system of a head mounted display, for example.

DESCRIPTION OF SYMBOLS 1 Optical lens 2 Optical member (1st optical member)
2a surface (optical surface, first optical surface)
3 Optical member (second optical member)
3a surface (optical surface, second optical surface)
4 Joining member 5 Optical functional member 5a Hologram optical element 11 Equal width portion 12 Narrow width portion 12a Side 12b Side 12c Curved portion 12d First curved portion 12e Second curved portion 12f Third curved portion 12g First curved portion 12h Second curved portion 12i Third curved portion 20 Optical sheet 20a Side 20b Side 20c Curved portion 20d First curved portion 20e Second curved portion 20f Third curved portion 20g First curved portion 20h Second curved portion cut curved portion 20i third curved portion 20L notch 20R segment region 20R ₁ protection, etc. width portion 20R ₂ narrow portion 21 resin sheet 22 hologram photosensitive material 23 sheet 40 optical sheet 40a side 40b side 40c curved portion 40L 40R segment region 40R ₁ equal width portion 40R ₂ narrow width portion 41 first resin sheet 42 optical adhesive sheet (adhesive sheet)
43 Holographic photosensitive material 44 Second resin sheet 50 HMD (head mounted display)
51 Video display device 52 Frame (support member)

Claims (10)

An optical lens manufacturing method for manufacturing an optical lens using an optical sheet in which a plurality of layers are held on a resin sheet,
The optical sheet forms an outer shape of the plurality of cut-out regions, and includes a cut for peeling the cut-out region from the resin sheet,
The cutout region has a narrow width portion that becomes narrower as it approaches an end portion in a direction perpendicular to the width direction in plan view,
The two sides defining the width of the narrow portion are connected via a curved portion having a radius of curvature of 0.5 mm or more located at the end portion,
The curved portion located at the end of the narrow portion is at the center position in the width direction,
The manufacturing method is as follows:
From the resin sheet of the optical sheet, the step of peeling the cut region from the end of the narrow part,
A process of attaching the cut-out region that has been peeled off to one optical surface of two optical members;
And a step of bonding the optical surfaces of the two optical members with a bonding member. The multiple layers include a hologram photosensitive material and a protective sheet from the resin sheet side,
The manufacturing method is as follows:
Further comprising the step of exposing the cut out region pasted to produce a hologram optical element;
2. The method of manufacturing an optical lens according to claim 1, wherein in the step of bonding with the bonding member, the optical surfaces of the two optical members are bonded with the bonding member via the hologram optical element. When the resin sheet is a first resin sheet,
The plurality of layers include, from the first resin sheet side, an adhesive sheet, a hologram photosensitive material, and a second resin sheet,
The manufacturing method is as follows:
Further comprising exposing the hologram photosensitive material of the optical sheet to produce a hologram optical element in the cutout region,
In the step of peeling the cut region, the cut region where the hologram optical element is formed is peeled from the first resin sheet,
In the step of attaching the cut region, the peeled cut region is attached to one optical surface of the two optical members via the adhesive sheet,
2. The optical lens manufacturing method according to claim 1, wherein, in the step of joining with the joining member, the optical surfaces of the two optical members are joined with the joining member via the cut-out region pasted. Method. 4. The method of manufacturing an optical lens according to claim 1, wherein an angle formed by the two sides defining the width of the narrow portion is 60 ° to 140 °. 5. 5. The method of manufacturing an optical lens according to claim 1, wherein the cut-out region has the narrow portion at both ends in a direction perpendicular to the width direction. 6. The method of manufacturing an optical lens according to claim 1, wherein, in the step of bonding with the bonding member, the bonding member is injected into a gap between the two optical members and cured. The step of bonding with the bonding member is characterized in that the bonding member is injected from the narrow portion side of the two optical members, and the bonding member flows in a direction perpendicular to the width direction. The manufacturing method of the optical lens as described in any one of. In the step of bonding with the bonding member, the bonding member is applied onto one optical surface of the two optical members, the two optical members are narrowed to a predetermined interval, and the bonding member is moved along the optical surface. The method of manufacturing an optical lens according to claim 1, wherein the bonding member is cured after being spread. 9. The optical lens according to claim 8, wherein in the step of bonding with the bonding member, the bonding member is applied to the outside in the vicinity of the end of the narrow width portion in a direction perpendicular to the width direction. Production method. The cut-out area has an equal width portion adjacent to the narrow width portion,
The narrow width portion is coincident with the width of the equal width portion at a connection point with the equal width portion,
The method of manufacturing an optical lens according to claim 1, wherein the curved portion of the narrow width portion has a shape that is convex toward the opposite side to the equal width portion.

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