Sight

Abstract

The objective is to provide a sighting device that increases the degree of freedom in positioning the light-emitting section and the display position of the aiming image, while suppressing the complexity of the configuration. [Solution] A aiming device is provided, comprising a housing, a light irradiating unit, and a display body for displaying a targeting light image, wherein the housing is provided with the light irradiating unit and the display body, the light irradiating unit is configured to irradiate the display body with light, the display body has an incident unit, an optical waveguide, and an outgoing unit, the incident unit is configured to guide the light irradiated from the light irradiating unit to the optical waveguide, the optical waveguide optically connects the incident unit and the outgoing unit so that the light incident from the incident unit is guided to the outgoing unit while undergoing total internal reflection in the optical waveguide, the outgoing unit is configured to emit the light that has propagated through the optical waveguide while undergoing total internal reflection to the outside of the display body, and the position of the outgoing unit corresponds to the display position of the targeting light image on the display body.

Description

Technical Field

[0001] The present invention relates to a sight.

Background Art

[0002] Sights are used for applications such as wild bird photography and celestial observation. For example, in wild bird photography, since the telephoto lens has a high magnification, the field of view is narrow, and it is difficult to directly capture the wild bird, which is the subject, in the finder. Therefore, a sight is attached to the top of the camera, and by aligning the aiming light image with the subject, the sight is used as a guide to lead the subject to the center in the finder. Also, in celestial observation, a sight is used as a guide when introducing a celestial body into the high-magnification field of view of a telescope. As such a sight, a form called a so-called dot sight, in which the aiming light from an aiming light source is reflected by an optical element such as a half mirror to form an aiming image, is known (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the conventional sight as described in Patent Document 1 above, the aiming light from the aiming light source is reflected by a plurality of optical elements (for example, a half mirror) and propagated in space. It is necessary to precisely arrange the plurality of optical elements at a desired angle, which complicates the configuration, and there is a problem that the degree of freedom in arranging the light irradiation unit and the display position of the aiming light image is restricted.

[0005] An object of the present invention is to provide a sight that increases the degree of freedom in arranging the light irradiation unit and the display position of the aiming light image while suppressing the complication of the configuration. [Means for solving the problem]

[0006] According to the present invention, a sighting device is provided, comprising a housing, a light irradiating unit, and a display body for displaying a targeting light image, wherein the housing is provided with the light irradiating unit and the display body, the light irradiating unit is configured to irradiate the display body with light, the display body has an incident unit, an optical waveguide, and an outgoing unit, the incident unit is configured to guide the light irradiated from the light irradiating unit to the optical waveguide, the optical waveguide optically connects the incident unit and the outgoing unit so that the light incident from the incident unit is guided to the outgoing unit while undergoing total internal reflection in the optical waveguide, the outgoing unit is configured to emit the light that has propagated through the optical waveguide while undergoing total internal reflection to the outside of the display body, and the position of the outgoing unit corresponds to the display position of the targeting light image on the display body.

[0007] According to the present invention, since the incident and outgoing sections are optically connected using an optical waveguide, it is possible to increase the degree of freedom in positioning the light irradiation section and the display position of the aiming light image while suppressing the complexity of the structure. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a perspective view of the aiming device 100 according to the embodiment, viewed from the rear oblique side. [Figure 2] Figure 2 is a perspective view of the sight 100 shown in Figure 1, viewed from the front at an oblique angle. [Figure 3] Figure 3A is a cross-sectional view of the housing 1B, which houses the light irradiation unit 3, adjustment mechanism 4, lens 5, and battery 6, along with an explanatory diagram showing how the five emitted lights are emitted from the display unit 2. Figure 3B is a side view of a modified configuration of the adjustment mechanism 4, viewed from one direction. Figure 3C is a side view of a modified configuration of the adjustment mechanism 4, viewed from a different direction than Figure 3B. [Figure 4]Figure 4A is a schematic diagram illustrating the arrangement of light propagating within the display body 2, the diffraction grating section 2b for changing the optical path through diffraction, and the output diffraction grating section 2c from which the output light is emitted. Figure 4B is a schematic diagram of a portion of the display body 2 shown in Figure 4A, cut by a plane parallel to the width direction and perpendicular to the height direction. It shows how light s incident from the incident diffraction grating section 2a propagates in the width direction while undergoing total internal reflection, and how a portion of it is sequentially diffracted in the height direction at the diffraction grating sections 2b1, 2b2, and 2b3. Figure 4C is a schematic diagram of a portion of the display body 2 shown in Figure 4A, cut by a plane parallel to the height direction and perpendicular to the width direction. It shows how light p2 diffracted by the diffraction grating section 2b2 propagates in the height direction while undergoing total internal reflection, and how a portion of it is sequentially emitted at the sub-diffraction grating section 2c4, main diffraction grating section 2c0, and sub-diffraction grating section 2c3. [Figure 5] In Figure 5, the central diagram schematically shows that five emitted lights can be seen when the eyeball is centered (within the reference range) relative to the target. In Figure 5, the diagrams to the left, right, and above and below the center diagram schematically show that when the eyeball is shifted by 3 mm in the left, right, up, or down directions, four emitted lights can be seen instead of five. [Modes for carrying out the invention]

[0009] Embodiments of the present invention will be described below with reference to the drawings. The various features shown in the embodiments below can be combined with each other. Furthermore, each feature constitutes an independent invention.

[0010] 1. Overall configuration of the aiming device The aiming device 100 according to this embodiment comprises a housing 1 shown in Figures 1 and 2, a display body 2 for displaying an aiming light image, and a light emitting unit 3, as shown in Figure 3, which is housed in a housing 1B of the housing 1 and configured to irradiate the display body 2 with light. In other words, the housing 1 is provided with the light emitting unit 3 and the display body 2. Each component will be described in detail below.

[0011] 1-1. Enclosure 1 As shown in Figures 1 and 2, the housing 1 comprises a display body holding section 1A, a housing section 1B, a window section 1C, and an operating section 1D. The housing 1 constitutes the outer shell of the aiming device 100, housing various components inside and having the function of holding the display body 2 in a predetermined position.

[0012] 1-1-1. Storage Section 1B In one embodiment, the housing section 1B of the housing 1 houses the light irradiation unit 3, the adjustment mechanism 4, the lens 5, and the battery 6, as shown in Figure 3. The housing section 1B is configured to protect these components from the external environment and to maintain a predetermined positional relationship. The lens 5 is provided to focus or parallelize the light irradiated from the light irradiation unit 3 toward the incident part (incident diffraction grating section 2a) of the display body 2, and can also be replaced with a diffractive optical element. Furthermore, while it is conceivable to arrange the adjustment mechanism 4, which allows adjustment of the position and direction of the light irradiation unit 3, on the exposed upper surface of the housing section 1B of the housing 1, in this embodiment, the adjustment mechanism 4 is housed inside the housing section 1B of the housing 1 in order to maintain a wide field of view in an open type configuration. The adjustment mechanism 4 is operated via an operation section 1D provided on the side of the housing section 1B of the housing 1.

[0013] 1-1-2.Display body holding part 1A The display body holder 1A is provided so as to protrude upward from the upper surface 1B1 of the housing 1B. The display body holder 1A has a frame-like structure for holding the display body 2. The width of the frame portion constituting the display body holder 1A is preferably set so as to ensure a wide field of view while maintaining strength. As shown in Figure 3, in one embodiment, the display body 2 is held by being inserted into a holding portion (for example, an insertion groove portion) formed in the display body holder 1A, but it is not limited to this.

[0014] 1-2. Light irradiation section 3 The light irradiation unit 3 is configured to irradiate the display unit 2 with light. In this embodiment, a laser diode is used as the light source forming the light irradiation unit 3. Laser diodes are suitable for clearly displaying the aiming light image because they emit light with high directivity and excellent monochromaticity. The color of the light emitted from the light irradiation unit 3 is not limited, but it is preferable to use red or green, which has high visibility even in bright environments. Red laser diodes are relatively inexpensive, and green laser diodes emit light in a wavelength range that is highly sensitive to human vision, so they can be appropriately selected depending on the usage environment and application.

[0015] 1-3.Display body 2 The display unit 2 is an optical element for displaying a targeting light image and has a wide-field-of-view open sight area 2A on its front side. The open sight area 2A can be defined as the area inside the inner surface of the display unit holding part 1A as a frame structure and above the upper surface 1B1 of the housing part 1B. As shown in Figure 4A, the display unit 2 has an incident diffraction grating part 2a as an incident part, an exit diffraction grating part 2c as an exit part, and an optical waveguide 20 as shown in Figures 4B and 4C.

[0016] The incident diffraction grating section 2a is configured to guide the light emitted from the light irradiation section 3 to the optical waveguide 20. The optical waveguide 20 optically connects the incident diffraction grating 2a and the exit diffraction grating 2c such that light incident from the incident diffraction grating 2a is guided to the exit diffraction grating 2c while undergoing total internal reflection within the optical waveguide 20. The emission diffraction grating 2c is configured to emit light that has propagated through the optical waveguide 20 while undergoing total internal reflection to the outside of the display unit 2. The position of the emission diffraction grating 2c corresponds to the display position of the aiming light image on the display unit 2. Furthermore, as shown in Figure 3, in one embodiment, the display unit 2 is positioned in front of the light-emitting unit 3 and the battery 6. This arrangement makes it possible to make the entire aiming device 100 more compact. Of course, the arrangement is not limited to this.

[0017] As shown in FIG. 4A, the display body 2 has a housing region Rg2 and an exposed region Rg1. The housing region Rg2 and the exposed region Rg1 may be distinguishable from each other in terms of the boundary of their regions as the shape of the display body 2. That is, for the housing region Rg2 of the display body 2, since it is protected by the housing portion 1B, it can be considered that the structural strength may be lower than that of the exposed region Rg1. The thickness of the housing region Rg2 is thinner than the thickness of the exposed region Rg1, and thus the two may be distinguished by this. In an example of the embodiment, the thickness of the exposed region Rg1 and the thickness of the housing region Rg2 are the same, and the distinction between them will be described as being made based on whether it is a portion disposed within the housing portion 1B or not.

[0018] That is, the exposed region Rg1 is a portion that is not housed within the housing portion 1B of the housing 1. In other words, the exposed region Rg1 is provided in the display body holding portion 1A of the housing 1 and is a region having a portion that is exposed to the outside of the sight 100. The above-described open site region 2A is formed in the exposed region Rg1. On the other hand, the housing region Rg2 is housed within the housing portion 1B of the housing 1 and is a region that is not exposed to the outside of the sight 100.

[0019] An incident diffraction grating portion 2a, which is an example of an incident portion, is provided in the housing region Rg2. That is, the incident diffraction grating portion 2a onto which the light irradiated from the light irradiation portion 3 is incident is disposed at a position shielded from the outside by the housing portion 1B. Thereby, the incident diffraction grating portion 2a is protected from the external environment (for example, dust, water droplets, etc.), and external light is prevented from directly entering the incident diffraction grating portion 2a. An emission diffraction grating portion 2c as an emission portion is provided in the exposed region Rg1. The exposed region Rg1 is exposed to the outside of the sight 100 while being held by the display body holding portion IA of the housing 1. Thereby, the user can simultaneously visually recognize the aiming light image emitted from the emission diffraction grating portion 2c while visually recognizing the object in front through the exposed region Rg1.

[0020] The display body 2 is formed of a material having a refractive index that allows for total internal reflection of light. The display body 2 is preferably made of a transparent or semi-transparent material, and is typically made of impact-resistant glass or plastic. Specifically, the refractive index of the display body 2 may be, for example, 1.40, 1.45, 1.50, 1.55, 1.60, 1.65, 1.70, 1.75, 1.80, 1.85, 1.90, 1.95, or 2.00, and may be within the range of two of these values. Specifically, for example, the refractive index of the display body 2 may be in the range of 1.4 to 2.0. The refractive index of the display body 2 is related to the propagation angle of light traveling through the optical waveguide 20 while undergoing total internal reflection, and efficient total internal reflection propagation can be achieved if the refractive index is within this range.

[0021] Specifically, the material of the display body 2 can be glass material, polymer material, ceramic material, crystalline material, or a combination thereof. Examples of glass materials include quartz glass, borosilicate glass, and soda-lime glass. Examples of polymer materials include polymethyl methacrylate (PMMA), polycarbonate (PC), cycloolefin polymer (COP), cycloolefin copolymer (COC), polyethylene terephthalate (PET), or polystyrene (PS). Examples of ceramic materials include translucent alumina. Examples of crystalline materials include sapphire, quartz, or calcium fluoride. These materials can be appropriately selected according to the desired optical properties (refractive index, transparency, durability, etc.).

[0022] 1-3-1.Incidence diffraction grating section 2a As described above, the housing area Rg2 of the display unit 2 is provided with an incident diffraction grating 2a as an incident section. The incident diffraction grating 2a is configured to guide the light irradiated from the light irradiation section 3 to the optical waveguide 20. More specifically, the incident diffraction grating 2a has the function of changing the direction of propagation of light by diffracting the light that is irradiated from the light irradiation unit 3 and incident on the surface of the display unit 2, and introducing the light into the optical waveguide 20 at an angle that allows it to propagate within the optical waveguide 20 under total internal reflection conditions. Preferably, the grating pitch and grating shape of the incident diffraction grating 2a are appropriately designed based on the wavelength and incident angle of the light irradiated from the light irradiation unit 3, as well as the refractive index of the optical waveguide 20.

[0023] 1-3-2. Optical waveguide 20 The optical waveguide 20 optically connects the incident diffraction grating 2a and the exit diffraction grating 2c so that light incident from the incident diffraction grating 2a is guided to the exit diffraction grating 2c while undergoing total internal reflection within the display body 2, and ultimately functions as an optical propagation path to guide the light to the exit diffraction grating 2c. The optical waveguide 20 has a structure that confines light inside the display body 2, and its material, shape, and structure are appropriately designed to achieve efficient light propagation.

[0024] In this embodiment, the direction of light propagating through the optical waveguide 20 is changed at least once within the display unit 2. Specifically, as shown in Figure 4B, light s incident from the incident diffraction grating 2a first propagates while undergoing total internal reflection in the lateral direction, and upon reaching the diffraction grating 2b, the diffraction action of the diffraction grating 2b changes the direction of a portion of the light, guiding it in the vertical direction as shown in Figure 4C. The remaining light that is not diffracted at the diffraction grating 2b continues to propagate while undergoing total internal reflection in the lateral direction, and is similarly partially diffracted at the next diffraction grating 2b. By adopting this configuration in which the direction of light propagates within the display unit 2 is changed, the degree of freedom in the relative positional relationship between the incident diffraction grating 2a and the exit diffraction grating 2c is increased. That is, it becomes possible to place the incident diffraction grating 2a and the exit diffraction grating 2c at any position in the display unit 2, and consequently, the degree of freedom in the placement of the light irradiation unit 3 and the display position of the aiming light image can be increased. The number of times the direction of light propagation within the display unit 2 is changed is not limited to once, but may be two or more times. Furthermore, the number of times the direction of light propagation within the display unit 2 is changed may be zero, but from the viewpoint of increasing the flexibility of the arrangement of various components, it is preferable to change it once or more.

[0025] In this embodiment, the display body 2 and the optical waveguide 20 contained therein may be a single-layer structure made of a single material, or a multilayer structure (laminated structure) in which multiple materials or layers are stacked. When the display body 2 has a multilayer structure, the optical waveguide 20 can be made up of at least one layer from among the multiple layers constituting the multilayer structure. Specifically, by making a particular layer of the multilayer structure a core layer (waveguide layer) and the adjacent layer a cladding layer, light can be confined within that particular layer and propagated by total internal reflection. In this way, by making a part of the display body 2 (at least one layer) function as an optical waveguide 20, different functions such as anti-reflective function, anti-fouling function, impact-reinforced function, or filter function that cuts out specific wavelengths can be assigned to the other layers, making it possible to further improve the optical performance and durability of the aiming device 100. Note that the propagation of light by total internal reflection is performed by utilizing the difference between the refractive index of the material constituting the optical waveguide 20 and the refractive index of the medium (air or other low refractive index layer, etc.) located around it.

[0026] In this embodiment, the optical waveguide 20 includes a region for propagating light in the lateral direction, as shown in Figure 4B, and a region for propagating light in the vertical direction, as shown in Figure 4C. A reflective diffraction grating 2b is provided at the connection point between the lateral optical waveguide and the vertical optical waveguide, and has the function of diffracting a portion of the light to change the optical path from the lateral direction to the vertical direction, while allowing the remaining light that was not diffracted to propagate in the lateral direction. Furthermore, in Figures 4B and 4C, etc., as a convenient example for the sake of explanation, the diffraction grating section 2b (and the incident diffraction grating section 2a and the exit diffraction grating section 2c) are shown as an example in which they are arranged on one surface of the display body 2 (or optical waveguide 20) (for example, the inner surface on the side closer to the user's eye). However, the arrangement of these diffraction grating sections is not limited to the illustrated configuration. For example, the diffraction grating section 2b, etc., may be provided on the other surface (outer surface) of the display body 2, or they may be formed to be embedded inside the display body 2, or at the interface between layers in the multilayer structure described above. In other words, each diffraction grating section may be provided at any position in the thickness direction of the display body 2, as long as it is a position that can perform the function of diffracting light and changing or emitting the optical path. Moreover, although the diffraction grating section 2b is exemplified as a reflective diffraction grating, a configuration in which a transmissive diffraction grating is used to branch or change the optical path may be adopted depending on the design of the optical waveguide.

[0027] 1-3-3. Emission Diffraction Grating The emission diffraction grating 2c is configured to emit light that has propagated through the optical waveguide 20 while undergoing total internal reflection to the outside of the display unit 2. The position of the emission diffraction grating 2c corresponds to the display position of the aiming light image on the display unit 2. That is, by emitting light from the position where the emission diffraction grating 2c is located, the user can see the aiming light image at that position. In this embodiment, the display unit 2 has a plurality of emission diffraction grating sections 2c. The plurality of emission diffraction grating sections 2c include at least one pair (five in one example of this embodiment) of emission diffraction grating sections whose emitted light propagation directions are different from each other. With this configuration, as will be described later, the number of visible targeting light images changes according to the user's eye position, and the user can recognize whether their eye position is correct or not.

[0028] (1) Main diffraction grating section 2c0 As shown in Figure 4A, each of the multiple emission diffraction grating sections 2c has a main diffraction grating section 2c0 and at least one sub-diffraction grating section 2c1 to 2c4. The emitted light from these diffraction grating sections includes emitted light t0 emitted from the main diffraction grating section 2c0, and emitted light t1 to emitted light t4 emitted from the sub-diffraction grating sections 2c1 to 2c4. In the following explanation, the emitted light will also be referred to as the aiming image or dot for the sake of clarity. Furthermore, the emitted light t0 will also be referred to as the primary aiming image or primary dot for the sake of clarity, and the emitted lights t1 to t4 will also be referred to as secondary aiming images or secondary dots for the sake of clarity.

[0029] The main diffraction grating 2c0 is positioned in the center of the exposed area Rg1 of the display body 2. The main diffraction grating 2c0 is configured to emit light so that the main aiming image (main dot) is displayed in the same position even if the position of the eyeball relative to the display body 2 is outside the reference range. In other words, since the light emitted from the main diffraction grating 2c0 is emitted in a relatively wide angular range, the main aiming image can be seen even if the user's eyeball position is slightly shifted. This is because the main diffraction grating 2c0 is configured to emit light in a direction perpendicular to the surface of the display body 2. Since light emitted from a direction perpendicular to the surface of the display body 2 reaches the user's eyeball from the same angular direction regardless of the position on the display body 2 from which it is emitted, the apparent direction of the main aiming image is considered to be substantially independent of the position of the main diffraction grating 2c0 on the display body 2. Due to these characteristics, the position of the emission diffraction grating 2c (main diffraction grating 2c0) is not limited to, for example, the center of the display body 2, and the degree of freedom in the position of the main diffraction grating 2c0 on the display body 2 is high. As a result, the main aiming light image is always visible to the user as a reference point for aiming.

[0030] (2) Sub-diffraction grating section 2c1 to sub-diffraction grating section 2c4 The output diffraction grating section 2c has a plurality of sub-diffraction grating sections 2c1 to 2c4 arranged around the main diffraction grating section 2c0. More specifically, as shown in Figure 4A, the plurality of sub-diffraction grating sections 2c1 to 2c4 are arranged above, below, to the left and to the right of the main diffraction grating section 2c0, respectively. That is, sub-diffraction grating section 2c1 is located to the right of the main diffraction grating section 2c0, sub-diffraction grating section 2c2 is located to the left of the main diffraction grating section 2c0, sub-diffraction grating section 2c3 is located above the main diffraction grating section 2c0, and sub-diffraction grating section 2c4 is located below the main diffraction grating section 2c0.

[0031] As described above, the main diffraction grating 2c0 is configured to emit light so that the main aiming image remains visible in the same position even if the eye position relative to the display body 2 is outside the reference range. Specifically, as shown in Figure 4C, the light t0 emitted from the main diffraction grating 2c0 is emitted in a direction parallel to the front-to-back width direction, that is, perpendicular to the surface of the display body 2. In contrast, the sub-diffraction gratings 2c1 to 2c4 are configured to emit light so that the sub-aiming image (sub-dot) becomes invisible when the eye position relative to the display body 2 is outside the reference range. Specifically, the light t1 to t4 emitted from the sub-diffraction gratings 2c1 to 2c4 are emitted in a direction different from the emission direction of the light t0 emitted from the main diffraction grating 2c0. In other words, the emitted light t1 to t4 from the sub-diffraction gratings 2c1 to 2c4 are emitted in a direction tilted by a predetermined angle (for example, angle β in Figure 4C) with respect to the emission direction of the emitted light t0. Therefore, if the user's eyeball position moves outside the reference range, the emitted light emitted in the tilted direction will no longer reach the user's eyeball, and the corresponding sub-targeting light image will no longer be visible.

[0032] With this configuration, the user can recognize that their eye position is within the correct reference range if the primary aiming image and all secondary aiming images (a total of five aiming images) are visible, and that their eye position is outside the reference range if some of the secondary aiming images are not visible. Furthermore, the user can recognize the direction in which their eye position is deviated depending on which secondary aiming image is not visible. In addition, the colors of the primary and secondary aiming images correspond to the colors of the light emitted from the laser diode of the light irradiation unit 3, and are all either red or green.

[0033] 1-4.Battery 6 Battery 6 is, for example, a power source for supplying power to the laser diode of the light irradiation unit 3, and is housed in the housing 1B of the housing 1, as shown in Figure 3. A AA battery is preferably used as battery 6. AA batteries are suitable as the power source for the aiming device 100 because they are highly versatile, readily available, and have sufficient power capacity. Note that battery 6 is not limited to AA batteries; for example, a rechargeable battery that can be charged via USB or the like may also be used. As described above, the display unit 2 is positioned in front of the light illuminator 3 and the battery 6. This arrangement allows the light illuminator 3 and the battery 6 to be grouped together at the rear of the housing 1B, while the display unit 2 is positioned at the front, thereby optimizing the overall weight balance and making the aiming device 100 more compact.

[0034] 1-5. Adjustment mechanism 4 As shown in Figure 3A, the adjustment mechanism 4 is provided in the housing section 1B of the housing 1. The adjustment mechanism 4 is configured to be operated by the user, for example, by operating the operating section 1D provided on the side of the housing 1 as shown in Figure 1. Specific examples of adjustments made by the adjustment mechanism 4 will be described below.

[0035] One first embodiment of the adjustment mechanism 4 is one in which the irradiation position of the light irradiation unit 3 is changed. In this embodiment, the adjustment mechanism 4 is configured to change the position at which the light irradiated from the light irradiation unit 3 enters the incident diffraction grating unit 2a by moving the light irradiation unit 3 in a plane perpendicular to the optical axis. Specifically, the adjustment mechanism 4 is configured to allow the light irradiation unit 3 to be moved in the lateral direction (defined, for example, the X direction) and the vertical direction (defined, for example, the Y direction). When the light irradiation unit 3 is moved in the X direction or the Y direction, the position at which the light irradiated from the light irradiation unit 3 enters the incident diffraction grating unit 2a changes. This makes it easier to adjust the irradiation position of the light irradiation unit 3 to the optimal position of the incident diffraction grating unit 2a, thereby increasing the light coupling efficiency at the incident diffraction grating unit 2a and optimizing the brightness of the aiming light image. In other words, the first embodiment of the adjustment mechanism 4 is suitable for adjustments aimed at optimizing the brightness of the aiming light image.

[0036] A second form of the adjustment mechanism 4 is one in which the direction of light irradiation from the light irradiation unit 3 is changed. The purpose of this second form is to change the display position of the aiming light image on the display unit 2. In other words, the adjustment mechanism 4 is configured to change the direction of light irradiation from the light irradiation unit 3 so that the display position of the aiming light image on the display unit 2 is changed. The specific configuration of the adjustment mechanism 4 according to the second form will be described below with reference to Figures 3B and 3C.

[0037] The adjustment mechanism 4 includes a mounting base 4A, a pivot support 4B1, and telescopic parts 4B2 and 4B3.

[0038] The mounting base 4A houses the light-emitting unit 3. The mounting base 4A is a member for holding the light-emitting unit 3 in a desired position, and the orientation of the optical axis of the light-emitting unit 3 changes according to the tilt of the mounting base 4A. The pivot support 4B1 has, for example, a spherical component provided to support the lower surface of the mounting base 4A. The pivot support 4B1 is configured to support the mounting base 4A in a tiltable manner. In other words, because the spherical component provided on the upper part of the pivot support 4B1 supports the lower surface of the mounting base 4A, the mounting base 4A can tilt in multiple directions. In this description, the pivot support 4B1 may also be configured so that its length in the vertical direction changes, similar to the telescopic part described later.

[0039] The telescopic parts 4B2 and 4B3 are actuators configured to change length in the vertical direction, and they support the lower surface of the mounting base 4A. The telescopic parts 4B2 and 4B3 are configured to change length independently of each other. As the amount of extension and retraction of the telescopic parts 4B2 and 4B3 changes, the mounting base 4A tilts with the pivot support 4B1 as the fulcrum, thereby changing the direction of the optical axis of the light irradiation unit 3 located on the mounting base 4A, i.e., the direction of light irradiation. For example, by making the lengths of the telescopic section 4B2 and the telescopic section 4B3 different, the mounting base section 4A is tilted in one direction, and the direction of light irradiation from the light irradiation section 3 is changed. This change in irradiation direction changes the angle at which the light irradiated from the light irradiation section 3 enters the incident diffraction grating section 2a, and the propagation angle of the light within the optical waveguide 20 changes. As a result, the direction of the light emitted from the exit diffraction grating section 2c changes, and the display position of the aiming light image on the display unit 2 is changed. The telescopic sections 4B2 and 4B3 can be extended and retracted via the operation section 1D provided on the side of the housing section 1B of the housing 1.

[0040] Furthermore, the configuration of the adjustment mechanism 4 in the second embodiment is not limited to the configuration shown in Figures 3B and 3C described above. Other mechanisms may be used as long as they allow the direction of light irradiation of the light irradiation unit 3 to be changed. For example, instead of the spherical part of the pivot support 4B1, a gimbal mechanism having multiple mutually orthogonal rotation axes may be used. Also, the number of telescopic parts is not limited to two; there may be one or three or more. Moreover, various telescopic mechanisms can be used as telescopic parts, such as screw-type actuators, piezoelectric actuators, or combinations of springs and screws.

[0041] The adjustment mechanism 4 may employ either the first form (a form that changes the illumination position) or the second form (a form that changes the illumination direction) described above, or it may employ a combination of both. When both are combined, it becomes possible to independently optimize the brightness of the aiming light image and change the display position of the aiming light image.

[0042] 2. Explanation of the aiming device's operation and light propagation, etc. The optical operation from the light irradiation unit 3 through the display unit 2, including its propagation and emission from the emission diffraction grating unit 2c, will be explained below with reference to Figures 4A to 4C. In this embodiment, the aiming device 100 employs a configuration that propagates light by utilizing the total internal reflection phenomenon in the optical waveguide 20 of the display unit 2.

[0043] Here, we will briefly explain the conditions for total internal reflection in the optical waveguide 20. Let the refractive index of the display body 2 (optical waveguide 20) be n, and the refractive index of the medium surrounding the optical waveguide 20 (e.g., air, a cladding layer with a low refractive index) be n². For light propagating within the optical waveguide 20 to undergo total internal reflection at the interface between the optical waveguide 20 and the surrounding medium, the angle of incidence θ with respect to the normal to the interface must be greater than or equal to the critical angle θc. Here, the angle of incidence θ is defined as the angle between the normal to the interface and the incident light ray. The critical angle θc is the angle that satisfies the relationship sinθc = n² / n = 1 / n, which can be derived from Snell's law (here, the medium surrounding the optical waveguide 20 is assumed to be air (refractive index 1)). In this embodiment, light propagating within the optical waveguide 20 is repeatedly incident on the interface of the optical waveguide 20 at an incident angle θ that satisfies the total internal reflection condition, and propagates within the optical waveguide 20 while repeatedly undergoing total internal reflection.

[0044] 2-1. Propagation of light from the incident diffraction grating 2a to the diffraction grating 2b Referring to Figures 4A and 4B, the process by which light emitted from the light irradiation unit 3 is introduced into the optical waveguide 20 via the incident diffraction grating unit 2a and propagates in the lateral direction will be explained. Light emitted from the light irradiation unit 3 is incident on the incident diffraction grating unit 2a provided on the surface of the display unit 2. The incident diffraction grating unit 2a has a periodic structure as a diffraction grating and has the function of diffracting incident light. When light is incident on the diffraction grating, diffracted light is generated in a specific direction depending on the grating pitch of the diffraction grating, the wavelength of the light, and the angle of incidence. The incident diffraction grating unit 2a is configured to change the direction of propagation of light by diffracting light incident from the outside, and to introduce it into the optical waveguide 20 at an angle that satisfies the total internal reflection condition. That is, the grating structure (grating pitch and grating shape) of the incident diffraction grating unit 2a is designed so that the diffracted light propagates in the optical waveguide 20 while satisfying the total internal reflection condition, based on the wavelength of the light emitted from the light irradiation unit 3 and the angle of incidence.

[0045] As shown in Figure 4B, the light s introduced into the optical waveguide 20 propagates in the lateral direction while repeatedly undergoing total internal reflection at the interface of the optical waveguide 20 at an incident angle θ that satisfies the total internal reflection condition. As shown in Figures 4A and 4B, the optical waveguide 20 is provided with diffraction gratings 2b (reflective diffraction gratings) for changing the direction of light propagation. More specifically, diffraction gratings 2b consist of diffraction gratings 2b1, 2b2, and 2b3, arranged along the width direction. These diffraction gratings 2b (diffraction gratings 2b1, 2b2, and 2b3) have the function of diffracting a portion of the light s that has propagated in the width direction while totally reflecting, thereby changing the optical path in the height direction. Specifically, light s first reaches the diffraction grating 2b1, where a portion of it is diffracted and propagates in the vertical direction as light p1. Light p1 propagates in the vertical direction while undergoing total internal reflection and reaches the sub-diffraction grating 2c1. The remaining light s that was not diffracted in the diffraction grating 2b1 continues to propagate in the horizontal direction while undergoing total internal reflection and reaches the diffraction grating 2b2. In the diffraction grating section 2b2, a portion of the light s is diffracted and becomes light p2 that propagates in the vertical direction. Light p2 propagates in the vertical direction while undergoing total internal reflection, sequentially reaching the sub-diffraction grating section 2c4, the main diffraction grating section 2c0, and the sub-diffraction grating section 2c3. The remaining light s that was not diffracted in the diffraction grating 2b2 propagates further in the lateral direction while undergoing total internal reflection and reaches the diffraction grating 2b3. In the diffraction grating 2b3, a portion of the light s is diffracted to become light p3 in the vertical direction. Light p3 propagates in the vertical direction while undergoing total internal reflection and reaches the sub-diffraction grating 2c2.

[0046] 2-2. Optical path modification in diffraction grating section 2b The principle of optical path change in the diffraction grating section 2b will now be explained in more detail. As described above, the diffraction grating section 2b is configured to diffract light propagating in the horizontal direction and change the direction of propagation of a portion of that light in the vertical direction. In other words, the diffraction grating section 2b has the function of deflecting light propagating from a specific direction (referred to here as the first direction, which corresponds to the horizontal direction in this embodiment) through diffraction and propagating it in a direction different from the first direction (referred to here as the second direction, which corresponds to the vertical direction in this embodiment). At this time, not all of the light incident on the diffraction grating section 2b is diffracted; some of the light is diffracted and propagates in the second direction, while the remaining light that is not diffracted continues to propagate in the first direction through total internal reflection. The lattice pitch, lattice shape, and lattice orientation direction of the diffraction grating section 2b are designed so that light incident from the lateral direction is diffracted in the vertical direction, and the diffracted light continues to propagate within the optical waveguide 20 while satisfying the total internal reflection condition. In other words, even after the optical path is changed in the diffraction grating section 2b, the light remains confined within the optical waveguide 20 and propagates in the vertical direction while repeatedly undergoing total internal reflection. In this embodiment, the diffraction grating section 2b is configured as a reflective diffraction grating. A reflective diffraction grating is a type of diffraction grating that reflects incident light while diffracting it, and is suitable for changing the optical path within the optical waveguide 20. Furthermore, the diffraction efficiency (the proportion of incident light that is diffracted) in each of the diffraction grating sections 2b1, 2b2, and 2b3 affects the brightness balance of the aiming light image emitted from each of the output diffraction grating sections 2c. It is preferable that the diffraction efficiency of each diffraction grating section 2b be appropriately designed according to the desired brightness balance.

[0047] 2-3. Light emission in the emission diffraction grating section 2c Referring to Figure 4C, the emission of light from the emission diffraction grating section 2c will be explained. Here, the main diffraction grating section 2c0, the secondary diffraction grating section 2c3, and the secondary diffraction grating section 2c4 will be used as examples, but the same principle applies to the secondary diffraction grating sections 2c1 and 2c2. As described above, the light p2, whose propagation direction is changed from the horizontal to the vertical direction in the diffraction grating section 2b, propagates through the optical waveguide 20 extending in the vertical direction while undergoing total internal reflection, and reaches the exit diffraction grating section 2c. In Figure 4C, the total internal reflection light propagating in the vertical direction within the optical waveguide 20 is shown as p2. The angle that the light propagating through the optical waveguide 20 makes with respect to the normal to the interface of the optical waveguide 20 (i.e., the angle of incidence that satisfies the total internal reflection condition) is shown as θ. Light p2 that reaches the output diffraction grating 2c undergoes diffraction at the output diffraction grating 2c, and a portion of it is emitted outside the optical waveguide 20. The remaining light p2 that is not emitted at the output diffraction grating 2c continues to propagate in the vertical direction while undergoing total internal reflection, and a portion of it is similarly emitted at the next output diffraction grating 2c. That is, light p2 reaches the sub-diffraction grating 2c4, the main diffraction grating 2c0, and the sub-diffraction grating 2c3 in that order, and a portion of it is sequentially emitted at each output diffraction grating as emitted light t4, emitted light t0, and emitted light t3, respectively. In Figure 4C, the emitted light emitted from the output diffraction grating 2c is shown as t0, t3, and t4. The diffraction phenomenon in a diffraction grating is determined by parameters such as the grating structure (grating pitch, etc.), the wavelength of light, and the angle of incidence. The direction of light emitted from the output diffraction grating section 2c (output angle) can be determined by the grating structure (grating pitch) of the output diffraction grating section 2c.

[0048] (1) Emission from the main diffraction grating section 2c0 The main diffraction grating section 2c0 is configured to emit a portion of the light p2 that has propagated through the optical waveguide 20 while undergoing total internal reflection, in a direction approximately perpendicular to the surface of the display unit 2 (parallel to the front-to-back width direction). If the grating pitch of the main diffraction grating section 2c0 is d0, the wavelength of light is λ, and the diffraction order is an integer m, the condition for light to be emitted in an approximately perpendicular direction (emission angle of 0 degrees) is expressed by the following equation. n × d0 × sinθ = mλ By designing the grating pitch d0 of the main diffraction grating 2c0 to satisfy this equation, the light emitted from the main diffraction grating 2c0 (emitted light t0) is emitted in a direction approximately perpendicular to the surface of the display unit 2. Therefore, even if the user's eye position is slightly off relative to the display unit 2, the main aiming light image can still be seen. The remaining light p2 that was not emitted from the main diffraction grating 2c0 continues to propagate in the vertical direction while undergoing total internal reflection, reaching the sub-diffraction grating 2c3.

[0049] (2) Emission from sub-diffraction gratings 2c3 and 2c4 The sub-diffraction gratings 2c3 and 2c4 are configured to emit a portion of the light p2 that has propagated through the optical waveguide 20 while undergoing total internal reflection, in a direction inclined with respect to the surface of the display unit 2. In Figure 4C, the inclination angle of the emitted light is shown by β. The sub-diffraction grating 2c4 (located below the main diffraction grating 2c0) is the first emission diffraction grating to which light p2 reaches, and is configured to emit a portion of light p2 as emission light t4 downwards from the horizontal plane at an angle β. If the grating pitch of the sub-diffraction grating 2c4 is d1, the condition for light to be emitted downwards at an angle β is expressed by the following equation. d1 × (n × sinθ + sinβ) = mλ The remaining light p2 that was not emitted in the sub-diffraction grating 2c4 continues to propagate in the vertical direction while undergoing total internal reflection, and reaches the main diffraction grating 2c0. The sub-diffraction grating 2c3 (located above the main diffraction grating 2c0) is configured to emit a portion of the light p2 that has passed through the main diffraction grating 2c0 as emitted light t3 upwards from the horizontal plane at an angle β. If the grating pitch of the sub-diffraction grating 2c3 is d2, the condition for light to be emitted upwards at an angle β is expressed by the following equation. d²×(n×sinθ-sinβ)=mλ

[0050] As can be understood from the above equation, the lattice pitch d1 of the sub-diffraction grating 2c4 is set to be smaller than the lattice pitch d0 of the main diffraction grating 2c0, and the lattice pitch d2 of the sub-diffraction grating 2c3 is set to be larger than the lattice pitch d0 of the main diffraction grating 2c0. By making the lattice pitches different in this way, light is emitted from the main diffraction grating 2c0 in a nearly vertical direction, and light is emitted from the sub-diffraction gratings 2c3 and 2c4 in an inclined direction. Because the light emitted from the sub-diffraction gratings 2c3 and 2c4 travels in a tilted direction, when the user's eyeball position moves outside the reference range, the emitted light no longer reaches the user's eyeball, and the corresponding sub-targeting image becomes invisible. Furthermore, since the diffraction efficiency of the sub-diffraction grating section 2c4, the main diffraction grating section 2c0, and the sub-diffraction grating section 2c3 affects the brightness balance of each aiming light image, it is preferable that the diffraction efficiency of each output diffraction grating section be appropriately designed according to the desired brightness balance.

[0051] (3) Emission from sub-diffraction gratings 2c1 and 2c2 The sub-diffraction gratings 2c1 (located to the right of the main diffraction grating 2c0) and 2c2 (located to the left of the main diffraction grating 2c0) are configured to emit light in a tilted direction, based on the same principle as the sub-diffraction gratings 2c3 and 2c4 described above. Light p1 diffracted by the diffraction grating 2b1 reaches the sub-diffraction grating 2c1 by propagating in the vertical direction while undergoing total internal reflection. Light p3 diffracted by the diffraction grating 2b3 reaches the sub-diffraction grating 2c2 by propagating in the vertical direction while undergoing total internal reflection. In other words, the sub-diffraction grating 2c1 emits light t1 in a direction tilted to the right, and the sub-diffraction grating 2c2 emits light t2 in a direction tilted to the left. As a result, as shown in Figures 4A and 5, the aiming light image t0 from the main diffraction grating 2c0 is at the center, and aiming light images t1 to t4 from the sub-diffraction gratings 2c1 to 2c4 are formed above, below, to the left and right of it.

[0052] 3. Description of the operation and effects of the embodiment In this embodiment, the display unit 2 comprises an incident diffraction grating section 2a as an incident section, an exit diffraction grating section 2c as an exit section, and an optical waveguide 20 connecting the incident and exit sections (in particular, the incident section and the optical waveguide in the width direction are arranged in a housing area (Rg2 in Figure 4A) that is not exposed to the outside by the housing section 1B of the housing 1, and only the exit section and the optical waveguide in the vertical direction are arranged in an exposed area (Rg1 in Figure 4A) that is exposed to the outside), thus enabling a smart configuration that maintains a wide field of view open type. Furthermore, in this embodiment, if the eyeball position relative to the display object is even slightly outside the reference range, the surrounding aiming light image relative to the central aiming light image will be hidden, thereby preventing this and allowing the eyeball position relative to the display object to be precisely aligned to the reference position.

[0053] In other words, in Figure 5, when the aiming light image t0 and the five spots of aiming light images t1 to t4 are visible, the user's eye position is correct, and by aligning the aiming light image t0 with the target, the target can be aimed correctly.

[0054] On the other hand, when only the four spots of the targeting light image t0 and targeting light images t1 to t3 are visible, the user can perceive that the eyeball position is 3 mm upward, and when only the four spots of the targeting light image t0 and targeting light images t1, t2, and t4 are visible, the user can perceive that the eyeball position is 3 mm downward. Similarly, when only the four spots formed by the aiming light image t0, t1, t3, and t4 are visible, the user can perceive that the eyeball is positioned 3 mm to the right. When only the four spots formed by the aiming light image t0, t2, t3, and t4 are visible, the user can perceive that the eyeball is positioned 3 mm to the left.

[0055] 4. Variations 4-1. Modification 1: Number of emission diffraction gratings The emission diffraction grating is positioned according to the aiming pattern of the sight, and is not limited to the five points mentioned above: the central position and the surrounding positions in the left, right, up, and down directions.

[0056] 4-2. Modification 2: Half-mirror Although the incident diffraction grating section 2a was described as an example of an incident section and the exit diffraction grating section 2c as an example of an exit section, a half-mirror may be used instead of the diffraction grating in the above-described embodiment. That is, as described above, the diffraction grating was used to have the function of branching the optical path, but instead of a diffraction grating, a half-mirror with the function of branching the optical path may be installed obliquely at the connection point between the optical waveguide in the lateral direction and the optical waveguide in the vertical direction. This allows, for example, half of the light incident on the half-mirror while totally reflecting through the optical waveguide in the lateral direction to be reflected and proceed to the optical waveguide in the vertical direction, while the remaining light passes through the half-mirror and continues to proceed further along the optical waveguide in the lateral direction.

[0057] 4-3. Modification 3: The color of the aiming light image is varied depending on the position of the emission diffraction grating. It is also possible to make some of the five spots in the aiming light image different colors. That is, in the embodiment described above, since the optical waveguide leading to the main diffraction grating 2c0 overlaps with the optical waveguide leading to at least a part of the sub-diffraction grating (sub-diffraction grating 2c3 and sub-diffraction grating 2c4), when a laser diode is used as the light irradiation unit 3, the five spots in the aiming light image t0 and the aiming light images t1 to t4 will all be the same color. Typically, all five spots will be red from the laser diode, or all will be green.

[0058] In contrast, if the optical waveguide 20 leading to the main diffraction grating section 2c0 is made independent so as not to overlap with the optical waveguide 20 leading to the sub-diffraction grating sections 2c1 to 2c4, and a separate light irradiation section 3 is provided in addition to the light irradiation section 3 corresponding to the sub-diffraction grating sections 2c1 to 2c4, the color of the central targeting image t0 and the surrounding targeting images t1 to t4 shown in Figure 5 can be made different colors. For example, the color of the central targeting image t0 can be made green for high visibility, and the color of the surrounding targeting images t1 to t4 can be made red. Conversely, the color of the surrounding targeting images t1 to t4 can be made green, and the color of the central targeting image t0 can be made red.

[0059] In this case, the optical waveguide 20 leading to the main diffraction grating section 2c0 does not overlap with other optical waveguides, and the light travels through a dedicated, bent waveguide without branching, undergoing total internal reflection. Therefore, an optical element corresponding to the diffraction grating section 2b along the optical path is unnecessary, and it is sufficient to provide a diffraction grating section corresponding to the main diffraction grating section 2c0 at the exit end.

[0060] 5. Addendum Various embodiments are illustrated below. The embodiments shown below can be combined with each other. [Note 1] It comprises a housing, a light-emitting section, and a display unit for displaying the aiming light image. The housing is provided with the light irradiation unit and the display unit, The light irradiation unit is configured to irradiate the display body with light, The display unit has an input section, an optical waveguide, and an output section. The incident portion is configured to guide the light emitted from the light irradiation portion to the optical waveguide. The optical waveguide optically connects the incident part and the outgoing part such that the light incident from the incident part is guided to the outgoing part while undergoing total internal reflection in the optical waveguide. A aiming device wherein the emission unit is configured to emit the light that has propagated through the optical waveguide while totally reflecting the light out of the display body, and the position of the emission unit corresponds to the display position of the aiming light image on the display body. [Note 2] The sighting device described in Appendix 1, The display body has a plurality of the ejection units, A sighting device comprising a plurality of emission units, each including at least one pair of emission units whose emitted light travels in directions different from each other. [Note 3] The sighting device described in Appendix 2, Each of the plurality of emission units has a main diffraction grating and at least one sub-diffraction grating. The aiming device has a aiming light image that corresponds to the main diffraction grating portion and a secondary aiming light image that corresponds to the secondary diffraction grating portion. [Note 4] The sighting device described in Appendix 3, The main diffraction grating is configured to emit light such that the main aiming image is displayed in the same position even if the position of the eyeball relative to the display body falls outside the reference range. The sub-diffraction grating is configured to emit light such that the sub-targeting light image disappears when the position of the eyeball relative to the display body falls outside a reference range. [Note 5] The sights described in Appendix 3 or Appendix 4, The aiming device wherein the emission unit has a plurality of sub-diffraction gratings arranged around the main diffraction grating. [Note 6] The sighting device described in Appendix 5, A sighting device in which multiple sub-diffraction gratings are arranged above, below, to the left and to the right of the main diffraction grating. [Note 7] A sighting device described in any one of the appendices 3 to 6, A sighting device in which the color of the primary aiming light image and the color of the secondary aiming light image are red or green. [Note 8] A sighting device described in any one of the appendices 3 to 7, A sighting device in which the color of the primary aiming light image and the color of the secondary aiming light image are different from each other. [Note 9] A sighting device described in any one of the appendices 1 to 8, The sight is composed of a glass material, a polymer material, a ceramic material, a crystalline material, or a combination thereof. [Note 10] A sighting device described in any one of the appendices 1 to 9, A sighting device in which the refractive index of the display element is in the range of 1.4 to 2.0. [Note 11] A sighting device described in any one of the appendices 1 to 10, The housing has a housing section and a display holder section protruding from the housing section. The display body has a containment area and an exposure area. The aforementioned storage area is housed within the aforementioned storage section. A sighting device wherein the exposed area is provided with the emission part, the exposed area is provided with the display body holding part, and the exposed area is exposed to the outside of the sighting device. [Note 12] The sighting device described in Appendix 11, The intake area is provided with the inlet portion, The light-emitting unit is a sighting device housed within the housing. [Note 13] The sights described in Appendix 11 or Appendix 12, Equipped with additional batteries, The aforementioned battery is housed within the aforementioned housing, and is part of a sighting device. [Note 14] The sighting device described in Appendix 13, The display unit is a sighting device positioned in front of the light emitting unit and the battery. [Note 15] A sighting device described in any one of the appendices 1 to 14, It also features an adjustment mechanism, The adjustment mechanism is provided in the housing, and the adjustment mechanism is configured to change the direction of light irradiation of the light irradiation unit so that the display position of the aiming light image on the display unit is changed. [Note 16] The sighting device described in Appendix 15, The adjustment mechanism comprises a mounting base, a pivot support, and an extendable / retractable section. The light irradiation unit is arranged on the aforementioned mounting base. The aforementioned pivot support is configured to support the aforementioned mounting base so that it can tilt, The aforementioned expandable portion supports the aforementioned mounting base and is configured to change in length. A sighting device in which the amount of extension or retraction of the telescopic part changes, causing the mounting base to tilt around the pivot point, thereby changing the direction of light irradiation of the light irradiation part. [Explanation of Symbols]

[0061] 100: Sight 1: Cabinet 1A:Display body holding part 1B: Containment area 1B1:Top surface 1C: Window section 1D:Operation unit 2:Display body 2A: Open site area 2a:Incidence grating section 2b: Diffraction grating 2b1: Diffraction grating section 2b2: Diffraction grating section 2b3: Diffraction grating section 2c: Emission diffraction grating section 2c0: Main diffraction grating section 2c1: Sub-diffraction grating 2c2: Sub-diffraction grating 2c3: Sub-diffraction grating 2c4: Sub-diffraction grating 20: Optical waveguide Rg1:Exposed area Rg2: Containment area 3: Light irradiation area 4:Adjustment mechanism 4A: Placement base 4B1: Axis branch 4B2: Telescopic part 4B3: Telescopic part 5: Lens 6:Battery

Claims

1. It comprises a housing, a light-emitting section, and a display unit for displaying the aiming light image. The housing is provided with the light irradiation unit and the display unit, The light irradiation unit is configured to irradiate the display body with light, The display unit has an input section, an optical waveguide, and a plurality of output sections. The incident portion is configured to guide the light emitted from the light irradiation portion to the optical waveguide. The optical waveguide optically connects the incident part and the outgoing part such that the light incident from the incident part is guided to the outgoing part while undergoing total internal reflection in the optical waveguide. The emission unit is configured to emit the light that has propagated through the optical waveguide while undergoing total internal reflection to the outside of the display body, and the position of the emission unit corresponds to the display position of the aiming light image on the display body. Each of the plurality of emission units has a main diffraction grating and at least one sub-diffraction grating. The aiming light image has a primary aiming light image corresponding to the primary diffraction grating and a secondary aiming light image corresponding to the secondary diffraction grating. The light emitted from the main diffraction grating and the light emitted from the sub-diffraction grating travel in different directions from each other. The main diffraction grating is configured to emit light such that the main aiming image is displayed in the same position even if the position of the eyeball relative to the display body falls outside the reference range. The sub-diffraction grating is configured to emit light such that the sub-targeting light image disappears when the position of the eyeball relative to the display body falls outside a reference range.

2. A sighting device according to claim 1, The sighting device has a plurality of sub-diffraction gratings arranged around the main diffraction grating.

3. The sighting device according to claim 2, A sighting device in which multiple sub-diffraction gratings are arranged above, below, to the left and to the right of the main diffraction grating.

4. A sighting device according to claim 1, A sighting device in which the color of the primary aiming light image and the color of the secondary aiming light image are red or green.

5. A sighting device according to claim 1, A sighting device in which the color of the primary aiming light image and the color of the secondary aiming light image are different from each other.

6. A sighting device according to any one of claims 1 to 5, The sight is composed of a glass material, a polymer material, a ceramic material, a crystalline material, or a combination thereof.

7. A sighting device according to any one of claims 1 to 5, A sighting device in which the refractive index of the display element is in the range of 1.4 to 2.

0.

8. A sighting device according to any one of claims 1 to 5, The housing has a housing section and a display holder section protruding from the housing section. The display body has a containment area and an exposure area. The aforementioned storage area is housed within the aforementioned storage section. A sighting device wherein the exposed area is provided with the emission part, the exposed area is provided with the display body holding part, and the exposed area is exposed to the outside of the sighting device.

9. A sighting device according to claim 8, The intake area is provided with the inlet portion, The light-emitting unit is a sighting device housed within the housing.

10. A sighting device according to claim 8, Equipped with additional batteries, The aforementioned battery is housed within the aforementioned housing, and is part of a sighting device.

11. A sighting device according to claim 10, The display unit is a sighting device positioned in front of the light emitting unit and the battery.

12. A sighting device according to any one of claims 1 to 5, It also features an adjustment mechanism, The adjustment mechanism is provided in the housing, and the adjustment mechanism is configured to change the direction of light irradiation of the light irradiation unit so that the display position of the aiming light image on the display unit is changed.

13. A sighting device according to claim 12, The adjustment mechanism comprises a mounting base, a pivot support, and an extendable / retractable section. The light irradiation unit is arranged on the aforementioned mounting base. The aforementioned pivot support is configured to support the aforementioned mounting base so that it can tilt, The aforementioned expandable portion supports the aforementioned mounting base and is configured to change in length. A sighting device in which the amount of extension or retraction of the telescopic part changes, causing the mounting base to tilt around the pivot point, thereby changing the direction of light irradiation of the light irradiation part.

Images