Optical device and camera device comprising same

Abstract

An optical device according to an embodiment of the present invention comprises: a light guide device guiding and irradiating incident light; a diffractive optical element disposed on one surface of the light guide device and diffracting the incident light to be incident to the light guide device; and an optical member separating the incident light from a light source in accordance with a wavelength to irradiate at different incident angles in accordance with the wavelength of the light, on the basis of a grating vector of the diffractive optical element.

Description

Optical device and camera device including the same

[0001] The present invention relates to an optical device and a camera device including the same, and more specifically, to an optical device utilizing the characteristics of a holographic optical element and a camera device including the same.

[0002] A diffractive optical element (DOE) is a device used to control the path of light by using diffraction caused by the periodic structure of a surface, rather than using refraction and reflection in an optical system.

[0003] Diffractive optical elements are used for optical pickup, such as objective lenses used in storage devices (e.g., DVDs, CDs), optical information processing, or as conductor lasers. However, the applications of these DOEs have been limited because they exhibit aberrations at specific wavelengths and lack wavelength selectivity. These limitations can be overcome through holographic optical elements (HOEs).

[0004] Holographic optical elements utilize the property of diffracting light rays based on the holographic principle and are designed to function as optical components such as lenses, prisms, mirrors, and diffusers, or as composite components that combine one or more of the functions of such optical components. More specifically, a holographic optical element is an optical device that records an interference pattern on a photosensitive material by interfering the object wave to be reproduced with a reference wave, which is another wave coherent with that light. Since the photosensitive material with the recorded interference pattern reproduces augmented image information using diffraction instead of reflection or refraction, such photosensitive materials are sometimes classified as a type of diffracting optical element.

[0005] As described above, holographic optical elements are generally manufactured by irradiating a photosensitive material with object waves and reference waves. Holographic optical elements manufactured in this way can be applied to Head-Up Displays (HUDs), cameras, and the like. When holographic optical elements are used in cameras, the illumination can be directed either through the holographic optical element or by being separated. In this case, efficiency can vary depending on the wavelength of the light, which can pose a problem.

[0006] The technical problem to be solved by the present invention is to provide an optical device capable of increasing light efficiency and a camera device including the same, wherein the light efficiency can vary depending on the wavelength and angle of incidence of light when using a diffractive optical element, particularly a holographic optical element.

[0007] In addition to this, the technical problems that the present invention aims to solve are not limited to those described above, and other technical problems may exist.

[0008] An optical device according to an embodiment of the present invention comprises a light guide device that guides and irradiates incident light, a diffraction optical element disposed on one surface of the light guide device to diffract the incident light and irradiate it to the light guide device, and an optical member that separates the light incident from a light source according to wavelength and irradiates the incident angle differently according to the wavelength of the light based on the grating vector of the diffraction optical element, wherein the optical member may have a diffraction angle that increases as the wavelength of the incident light becomes shorter.

[0009] In an optical device according to an embodiment of the present invention, the wavelength of light irradiated from above the optical member may be shorter than the wavelength of light irradiated from below the optical member.

[0010] In an optical device according to an embodiment of the present invention, the optical member may be a prism.

[0011] In an optical device according to an embodiment of the present invention, the prism may be a prism reflection type or a prism sheet type.

[0012] In an optical device according to an embodiment of the present invention, the optical member may be a lens.

[0013] In an optical device according to an embodiment of the present invention, when the light source is a plurality of light sources, the optical member may include a lens and a prism.

[0014] In an optical device according to an embodiment of the present invention, the prism may be a prism sheet.

[0015] In an optical device according to an embodiment of the present invention, the prism may be composed of a plurality of prisms.

[0016] In an optical device according to an embodiment of the present invention, the plurality of light sources may be light sources with different wavelengths.

[0017] An optical device according to an embodiment of the present invention may further include an input / output diffraction element disposed in the light guide device for diffracting incident light and irradiated light, and an output diffraction element disposed in the light guide device for diffracting irradiated light.

[0018] In an optical device according to an embodiment of the present invention, the light guide device may include a substrate.

[0019] A camera device according to an embodiment of the present invention may include an optical device, a light source unit including the light source, and a light receiving unit that receives light irradiated from the light guide device.

[0020] According to an embodiment of the present invention, light can be irradiated separately according to the wavelength of light irradiated from a light source, thereby increasing light efficiency.

[0021] According to an embodiment of the present invention, an optical device utilizing the features of a holographic optical element and a camera device including the same can be provided.

[0022] In addition to these, the effects obtainable from the present invention are not limited to those mentioned above, and other unmentioned effects will be clearly understood by those skilled in the art to which the present invention belongs from the description below.

[0023] FIG. 1 is a block diagram of a camera module including an optical device according to one embodiment of the present invention.

[0024] FIG. 2 is a drawing showing the configuration of a camera module according to one embodiment of the present invention.

[0025] Figure 3 is a graph showing the characteristics of a holographic optical element (HOE) according to the wavelength of light as an example.

[0026] FIGS. 4a to 4c are drawings showing the diffraction angle according to the wavelength of light in an optical member according to an embodiment of the present invention.

[0027] FIGS. 5 to 7 are drawings showing optical members according to various embodiments of the present invention.

[0028] FIGS. 8 to 10 are drawings showing an optical member to which a plurality of light sources are applied according to various embodiments of the present invention.

[0029] FIG. 11 is a drawing showing optical members at different positions as another embodiment of the present invention.

[0030] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings.

[0031] However, the technical concept of the present invention is not limited to some of the described embodiments but can be implemented in various different forms, and within the scope of the technical concept of the present invention, one or more of the components among the embodiments may be selectively combined or substituted.

[0032] In addition, terms used in the embodiments of the present invention (including technical and scientific terms) may be interpreted in a sense that is generally understood by those skilled in the art to which the present invention belongs, unless explicitly and specifically defined otherwise. Terms that are commonly used, such as terms defined in advance, may be interpreted in consideration of their meaning in the context of the relevant technology.

[0033] Furthermore, the terms used in the embodiments of the present invention are for the purpose of describing the embodiments and are not intended to limit the present invention.

[0034] In this specification, the singular form may include the plural form unless specifically stated otherwise in the text, and when described as "at least one of A and B and C (or more than one)," it may include one or more of all combinations that can be formed from A, B, and C.

[0035] In addition, terms such as first, second, A, B, (a), (b), etc. may be used when describing the components of the embodiments of the present invention.

[0036] These terms are intended merely to distinguish a component from other components and are not limited by the nature, order, sequence, etc., of the said component.

[0037] And, where it is stated that a component is 'connected', 'combined', or 'joined' to another component, this may include not only cases where the component is directly connected, combined, or joined to the other component, but also cases where it is 'connected', 'combined', or 'joined' due to another component located between the component and the other component.

[0038] Furthermore, when described as being formed or placed "above or below" each component, "above" or "below" includes not only cases where two components are in direct contact with each other, but also cases where one or more other components are formed or placed between the two components. Additionally, when expressed as "above or below," it may include the meaning of a downward direction as well as an upward direction relative to a single component.

[0039] FIG. 1 is a block diagram of a camera module including an optical device according to an embodiment of the present invention, and FIG. 2 is a diagram showing the configuration of a camera module according to an embodiment of the present invention.

[0040] Referring to FIG. 1, the camera module (100) may include a light source unit (110), a light guide device (120), an optical member (130), a light receiving unit (130), and a control unit (140).

[0041] The light source unit (110) is configured to irradiate (or emit) light and can irradiate light onto an object by means of a control signal. The light irradiated onto the object can be reflected and incident on the light receiving unit (130).

[0042] According to one embodiment, the light source unit (110) may include at least one light source. The at least one light source may irradiate light of a predetermined wavelength band or light having a predetermined center wavelength. Additionally, the light source of the light source unit (110) may irradiate light of a predetermined pattern according to a pre-designed algorithm. The light source unit (110) may irradiate light under the control of the control unit (140).

[0043] In the following description, output light or incident light refers to light that is irradiated from the light source unit (110) and provided to an object, and input light or reflected light may refer to light that is irradiated from the light source unit (110), reaches the object, is reflected from the object, and is input to the light receiving unit (130). Additionally, from the perspective of the object, output light may be incident light, and input light may be reflected light.

[0044] At least one light source of the light source unit (110) can irradiate light of a predetermined wavelength band. For example, the wavelength of the light irradiated from the light source may be infrared light with a wavelength of 770 nm to 3000 nm. In addition, the wavelength of the light irradiated from the light source may be visible light with a wavelength of 380 nm to 770 nm. In addition, the wavelength of the light irradiated from the light source may be infrared light with a wavelength of 850 nm to 1050 nm. Furthermore, the light source of the light source unit (110) may irradiate light other than the aforementioned wavelength range.

[0045] The light source may include at least one of a light-emitting diode (LED), an organic light-emitting diode (OLED), a laser diode (LD), a vertical-cavity surface-emitting laser (VCSEL), a plasma lamp, a fluorescent lamp, a xenon lamp, a halogen lamp, and a neon lamp.

[0046] According to one embodiment, a collimator lens can be applied to a light source. For example, a collimator lens may be applied to each LED, or a single collimator lens may be applied to multiple LEDs.

[0047] The light guide device (120) may be positioned adjacent to the light source unit (110) and the light receiving unit (130). The light guide device (120) can guide light irradiated from the light source unit (110) and deliver it to an object. The light guide device (120) can also guide light reflected from the object back to the light receiving unit (130). In this way, the light guide device (120) can be configured to control light and move it along a desired path. That is, the light guide device (120) can deliver light to an object and receive light reflected from the object. Accordingly, the light guide device (120) can be configured to help light from the camera module (100) reach the sensor accurately, or to guide light along a specific path so that optical information is accurately delivered.

[0048] These light guide devices (120) may be made of materials such as glass, polymer, or silicon. In addition, the light guide devices (120) may include various materials capable of light guiding.

[0049] Additionally, the light guide device (120) can transmit light in a desired direction using diffraction. Accordingly, the light guide device (120) may include a diffraction optical element (160) for determining the path of light on a substrate that is a waveguide. The diffraction optical element (160) may be, for example, a holographic optical element (HOE). The light guide device (120) may include a plurality of diffraction optical elements as described below. The plurality of diffraction optical elements may be composed of holographic optical elements.

[0050] According to one embodiment, a holographic optical element diffracts light using an interference pattern generated through laser interference, thereby controlling light of a specific wavelength or diffracting it in a desired direction. Bragg's Law is applied during this diffraction process, and the diffraction angle can be determined according to the wavelength of the light and the structure of the holographic optical element.

[0051] A holographic optical element may include an interference pattern recorded on a transparent substrate. As previously mentioned, the transparent substrate serves as a waveguide and can be made of various materials such as glass, plastic, or polymer. The interference pattern of the holographic optical element can be precisely designed within or on the surface of the substrate to guide light in a specific direction. Furthermore, holographic optical elements can be classified into transmissive types, where light diffracts as it passes through, and reflective types, where light diffracts as it is reflected. Accordingly, the position of the holographic optical element on the substrate can change. High-resolution images can be provided by precisely controlling light through such a holographic optical element. Additionally, holographic optical elements can support high-speed data transmission in optical communication through wavelength separation and coupling. Moreover, since holographic optical elements are lighter and thinner than conventional lenses or mirrors, they can provide miniaturized camera modules.

[0052] The light receiving unit (130) can also be located adjacent to the light guide device (120), just like the light source unit (110). Additionally, an additional lens may be placed between the light receiving unit (130) and the light guide device (120).

[0053] The control unit (140) can control the operation of the light source unit (110) and the light receiving unit (130). The control unit (140) can generate depth information based on an image generated by the light receiving unit (130) or transmit and receive image information with other electronic devices, such as a vehicle. This control unit (140) can control the operation within the camera module and can also communicate with a processor, etc., within an external electronic device, such as a vehicle.

[0054] The control unit (140) may include a processor, a microcontroller (MCU), a Field Programmable Gate Array (FPGA), an Application Specific Integrated Circuit (ASIC), etc., and may also be implemented in the form of an Application Processor (AP) of various electronic devices.

[0055] The optical member (150) can adjust the angle of incidence of light irradiated from the light source unit (110) to the light guide device (120), specifically the diffractive optical element (160), differently according to the wavelength of the light. The angle of incidence to the diffractive optical element (160) can be based on a grating vector included in the diffractive optical element. The optical member (150) may include, for example, at least one of a prism, a lens, and a prism sheet. According to one embodiment, the optical member (150) may be composed of multiple units, and any configuration capable of emitting light at a predetermined angle according to the wavelength may be the optical member (150).

[0056] Referring to FIG. 2, the optical device (170) may include a light guide device (120), a first diffraction optical element (160-1), a second diffraction optical element (160-2), a third diffraction optical element (160-3), and an engineering member (150).

[0057] The first diffraction optical element (160-1) may be an input diffraction optical element, the second diffraction optical element (160-2) may be an output diffraction optical element, and the third diffraction optical element (160-3) may be an input / output output diffraction optical element. The first diffraction optical element (160-1), the second diffraction optical element (160-2), and the third diffraction optical element (160-3) may be placed in a light guide device (120) which is a waveguide. According to one embodiment, the light guide device (120) may be a substrate (WG). The first diffraction optical element (160-1), the second diffraction optical element (160-2), and the third diffraction optical element (160-3) correspond to either a light-transmitting type or a light-reflecting type, and may be located on either one side (e.g., the top surface) or the other side (e.g., the bottom surface) of the light guide device (120). The first diffraction optical element (160-1), the second diffraction optical element (160-2), and the third diffraction optical element (160-3) may be spaced apart from each other.

[0058] The first diffraction optical element (160-1) may be configured such that the incident angle of the optical axis in the light irradiated from the light source (110) varies according to the wavelength based on the grating vector included in the first diffraction optical element (160-1). The first diffraction optical element (160-1) may be composed of a plurality of diffraction optical elements or may include a plurality of regions.

[0059] In an example, light emitted from a light source (110) is incident on an optical member (150) and may be incident on a first diffractive optical element (160-1) at an angle of emission different according to the wavelength of the light. Based on the grating vector of the first diffractive optical element (160-1), the light incident at an angle of incidence different according to the wavelength of the light may be guided into a light guide device (120).

[0060] The first diffracting optical element (160-1) diffracts light provided from the light source unit (110) and guides it to the light guide device (120), and the light guided into the light guide device (120) can be provided to the third diffracting optical element (160-3).

[0061] The third diffracting optical element (160-3) can diffract light guided from the first diffracting optical element (160-1) to the light guide device (120) into an object, and diffract light reflected from the object and guide it into the light guide device (120).

[0062] The object may be various objects outside the camera module or the light guide device (120). That is, the object may be various objects that can be detected or recognized through the camera module, and may include people, cars, animals, buildings, etc.

[0063] Subsequently, light emitted from the third diffraction optical element (160-3) can be reflected from the object and received by the third diffraction optical element (160-3). At this time, the light provided to the third diffraction optical element (160-3) can be diffracted at the input / output diffraction element third diffraction optical element (160-3), thereby changing the light path.

[0064] Accordingly, the third diffracting optical element (160-3) can diffract light reflected from an object and guide it to the light guide device (120). At this time, the light diffracted by the third diffracting optical element (160-3) and guided to the light guide device (120) can be guided to or provided to the second diffracting optical element (160-2).

[0065] The second diffracting optical element (160-2) can diffract light reflected from an object and guided to the light guide device (120) by the third diffracting optical element (160-3), and guide it to or emit it to the light receiving unit (130). At this time, the light diffracted by the second diffracting optical element (160-2) and guided to the light receiving unit (130) is incident on the light receiving unit (130) and can be converted into image information.

[0066] Figure 3 is a graph showing the characteristics of a holographic optical element (HOE) according to the wavelength of light as an example.

[0067] Referring to Fig. 3, the x-axis represents the wavelength of light, and the y-axis represents the angle of incidence of light. An angle of incidence of 0 degrees means an angle parallel to the normal, that is, perpendicular to the plane of incidence; a positive angle of incidence means that the light is incident from top to bottom, and a negative angle of incidence means that the light is incident from bottom to top.

[0068] According to Fig. 3, when the angle of incidence of light is 0 degrees, only light of a wavelength of 530 nm is emitted, and light of other wavelengths may not be emitted. Strictly speaking, it is not that no light is emitted, but the amount of emitted light may be extremely small. Although the amount of light emitted for wavelengths other than 530 nm is small, if we examine the diffraction angle according to the wavelength of light, it can be seen that the shorter the wavelength of light (X-axis in Fig. 3), the larger the diffraction angle (Y-axis in Fig. 3).

[0069] FIGS. 4a to 4c are drawings showing the diffraction angle according to the wavelength of light in an optical member according to an embodiment of the present invention.

[0070] Referring to FIGS. 4a to 4c, the optical element may be a prism. The prism (410, 420, 430) which is the optical element may have different angles on its left side and right side. FIG. 4a shows a prism (410) in which the angle of the left side (411) is 30 degrees and the angle of the right side (412) is 0 degrees, and FIGS. 4b and 4c show a prism (420, 430) in which the angle of the left side (421, 431) is 30 degrees and the angle of the right side (422, 432) is 20 degrees.

[0071] In Fig. 4a, when the incident light is 1050 nm (Red), 500 nm (Green), and 350 nm (Blue), the diffraction angles are 18.89 degrees, 19.53 degrees, and 20.32 degrees, respectively. In Fig. 4b, when the incident light is 1050 nm (Red), 500 nm (Green), and 350 nm (Blue), the diffraction angles are 34.73 degrees, 36.32 degrees, and 38.39 degrees, respectively. In Fig. 4c, when the incident light is 1050 nm (Red), 950 nm (Green), and 850 nm (Blue), the diffraction angles are 34.73 degrees, 34.88 degrees, and 35.05 degrees, respectively.

[0072] In other words, combining Figures 4a to 4c, it can be seen that the shorter the wavelength of light incident on the optical element, the larger the diffraction angle becomes.

[0073] Based on FIGS. 3 to 4c, the wavelength of light that can be emitted varies depending on the angle of incidence of the light, and the diffraction angle may vary depending on the wavelength of the light. Therefore, in order to increase the efficiency of the emitted light, the present invention proposes an optical member that can vary the angle of incidence depending on the wavelength of the light.

[0074] FIGS. 5 to 7 are drawings illustrating optical members according to various embodiments of the present invention. Specifically, FIG. 5 shows an example using a lens as an optical member, FIG. 6 shows an example using a prism as an optical member, and FIG. 7 shows an example using a prism sheet as an optical member.

[0075] Referring again to FIG. 5, the optical member may include a lens (150). The lens (150) may, for example, have a flat portion where light is incident and a curvature where light is emitted. Due to the curvature of the lens (150), when light incident on the lens (150) is emitted, the angle of emission may vary depending on the wavelength of the light. According to one embodiment, the curvature of the lens (150) may vary depending on the required angle of incidence of the light incident on the diffractive optical element (160). The required angle of incidence may vary depending on the wavelength of the light.

[0076] According to one embodiment, the incident angle of light incident on the lens (150) may be constant regardless of the wavelength of the light, but the incident angle of light emitted through the lens (150) may vary depending on the wavelength of the light. The light emitted through the lens (150) may be incident on a diffractive optical element (160), and the light incident on the diffractive optical element (160) may be diffracted by the diffractive optical element (160) and incident on a light guide device (120) in which the diffractive optical element (160) is placed.

[0077] Referring to FIG. 6, the optical member may include a prism (150). According to one embodiment, the prism (150) may be a reflective prism. That is, in FIG. 6, the direction of light incident on the reflective prism (150) may be changed by the reflective prism (150) and emitted. More specifically, light incident on one surface of the reflective prism (150) may be reflected inside the reflective prism (150) and emitted from one surface of the reflective prism (150). The one surface of the reflective prism (150) into which light is incident and the one surface of the reflective prism (150) from which light is emitted may be different surfaces, but are not limited thereto.

[0078] According to one embodiment of the present invention, the incident angle of light incident on the reflective prism (150) may be constant regardless of the wavelength of the light, but the incident angle of light emitted through the reflective prism (150) may vary depending on the wavelength of the light. The light emitted by the reflective prism (150) may be incident on the diffractive optical element (160), and the light incident on the diffractive optical element (160) may be diffracted by the diffractive optical element (160) and incident on the light guide device (120) in which the diffractive optical element (160) is placed.

[0079] Referring to FIG. 7, the optical member may include a prism sheet (150). The prism sheet (150) may be composed of a thin film that refracts light. By using the prism sheet (150), the space, thickness, or volume occupied compared to a prism may be reduced.

[0080] According to one embodiment, the incident angle of light incident on the prism sheet (150) may be constant regardless of the wavelength of the light, but the incident angle of light emitted through the prism sheet (150) may vary depending on the wavelength of the light. The light emitted through the prism sheet (150) may be incident on a diffractive optical element (160), and the light incident on the diffractive optical element (160) may be diffracted by the diffractive optical element (160) and incident on a light guide device (120) in which the diffractive optical element (160) is placed.

[0081] FIGS. 8 to 10 are drawings showing an optical member to which a plurality of light sources are applied according to various embodiments of the present invention.

[0082] Referring to FIG. 8, a plurality of light sources (not shown) may each irradiate light of different wavelengths, and the optical member may include a lens (151) and a prism (152). The light source may be, for example, an LED that irradiates light of different wavelengths. Light emitted from the light source may first be incident on the lens (151). The angle at which each of the plurality of lights is emitted from the lens (151) may be determined. That is, the angle at which each of the plurality of lights is emitted may be determined by the arrangement of the lens (151). For example, the angle at which the plurality of lights of different wavelengths are emitted from the lens (151) may be the same.

[0083] According to one embodiment, light emitted from the lens (151) may be emitted after being incident on the prism (152). The angle of emission of the light emitted from the prism (152) may vary depending on the wavelength. The angle of emission of the light emitted from the prism (152) may be constant depending on the wavelength, and this may be determined by the arrangement of the prism (152). The path of the light emitted from the prism (152) may be incident on the diffracting optical element (160) as described in FIGS. 5 to 7, diffracted, and then incident on the light guide device (120).

[0084] Referring to FIG. 9, a plurality of light sources (not shown) may each irradiate light of different wavelengths, and the optical member may include a lens (151) and a prism sheet (152). The light source may be, for example, an LED that irradiates light of different wavelengths. Light emitted from the light source may first be incident on the lens (151). The angle at which each of the plurality of lights is emitted from the lens (151) may be determined. That is, the angle at which each of the plurality of lights is emitted may be determined by the arrangement of the plurality of light sources and the lens (151). For example, the angle at which the plurality of lights of different wavelengths are emitted from the lens (151) may be the same.

[0085] According to one embodiment, light emitted from the lens (151) may be emitted after being incident on the prism sheet (152). The angle of emission of the light emitted from the prism sheet (152) may vary depending on the wavelength. The angle of emission of the light emitted from the prism sheet (152) may be constant depending on the wavelength, and this may be determined by the arrangement of the prism sheet (152). The path of the light emitted from the prism (152) may be incident on the diffracting optical element (160) as described in FIGS. 5 to 8, diffracted, and then incident on the light guide device (120).

[0086] Referring to FIGS. 8 and 9, by using a prism sheet instead of a prism, at least one of the size, thickness, and volume that the optical member can occupy can be reduced, thereby allowing the optical member to be miniaturized.

[0087] Referring to FIG. 10, a plurality of light sources (not shown) may each irradiate light of different wavelengths, and the optical member may include a lens (151) and a plurality of prisms (152, 153). The light source may be, for example, an LED that irradiates light of different wavelengths. Light emitted from the light source may first be incident on the lens (151). The angle at which each of the plurality of lights is emitted from the lens (151) may be determined. That is, the lens (151) may be arranged so that the angle at which the plurality of lights are emitted is constant. For example, the angle at which the plurality of lights of different wavelengths are emitted from the lens (151) may be the same. The light emitted from the lens (151) may be incident on the first prism (152), and the light incident on the first prism (152) may be emitted from the first prism (152) and incident on the second prism (153). The emission angle of light emitted from the second prism (153) may be constant according to the wavelength. That is, light irradiated from a plurality of light sources and incident on the lens (151) may have its emission angle determined according to the wavelength of the light by the arrangement of the lens (151) and the plurality of prisms (152, 153). The light emitted from the second prism (153) may be incident on a diffracting optical element (160) as described above in FIGS. 5 to 9, diffracted, and then incident on a light guide device (120).

[0088] FIG. 11 is a drawing showing optical members at different positions as another embodiment of the present invention.

[0089] In FIG. 11, the optical element may be a prism (150). As described in FIG. 6, the prism (150) may be a reflective prism, and the direction of light incident on the reflective prism (150) may be changed by the reflective prism (150) and emitted. In addition, the angle at which light incident on the reflective prism (150) is emitted from the reflective prism (150) may vary depending on the wavelength of the light.

[0090] Referring to FIG. 11, light incident on the reflective prism (150) may be light emitted from a light source (not shown). Light that has been redirected by the reflective prism (150) may be emitted from the reflective prism (150) and reach an object directly. That is, light emitted from the reflective prism (150) may reach an object directly without passing through the light guide device (120). Light that reaches an object may be reflected by the object and incident on the light guide device (120).

[0091] In FIG. 11, the optical element is described as a prism (150), but is not limited thereto. The optical element described in FIG. 5 to FIG. 10 above may also be used.

[0092] Although the invention has been described above with reference to embodiments, this is merely illustrative and does not limit the invention. Those skilled in the art will understand that various modifications and applications not exemplified above are possible within the scope of the essential characteristics of the embodiments. For example, each component specifically shown in the embodiments may be modified and implemented. Furthermore, differences related to such modifications and applications should be interpreted as being included within the scope of the invention as defined in the appended claims.

Claims

1. A light guide device that guides and irradiates incident light; A diffraction optical element disposed on one surface of the light guide device and diffracting incident light to cause it to be incident on the light guide device; and It includes an optical member that separates light incident from a light source according to wavelength and irradiates the incident angle differently according to the wavelength of the light based on the grating vector of the diffraction optical element. The above optical element is an optical device in which the diffraction angle increases as the wavelength of the incident light becomes shorter.

2. In Paragraph 1, An optical device in which the wavelength of light irradiated from above the optical member is shorter than the wavelength of light irradiated from below the optical member.

3. In Paragraph 1, An optical device in which the above optical element is a prism.

4. In Paragraph 3, The above prism is an optical device that is of the prism reflection type or prism sheet type.

5. In Paragraph 1, The above optical member is a lens, an optical device.

6. In Paragraph 1, When the above light source is a plurality of light sources, The above optical member is an optical device comprising a lens and a prism.

7. In Paragraph 6, The above prism is an optical device that is a prism sheet.

8. In Paragraph 6, The above prism is an optical device composed of a plurality of prisms.

9. In Paragraph 6, An optical device in which the above plurality of light sources are light sources with different wavelengths.

10. In Paragraph 1, Input / output diffraction elements disposed in the light guide device above for diffracting incident light and irradiated light; and An optical device further comprising an output diffraction element disposed in the light guide device above to diffract light irradiated thereon.

11. In Paragraph 1, The above light guide device is an optical device comprising a substrate.

12. An optical device according to any one of claims 1 to 11; A light source unit including the above light source; and A camera device comprising a light receiving unit that receives light irradiated from the light guide device.

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