Waveguide device

Abstract

The present specification discloses waveguides and uses thereof. For example, the present specification discloses a waveguide device for implementing virtual reality (VR), augmented reality (AR), mixed reality (MR), or augmented reality (XR), etc. The present specification can disclose a waveguide device capable of achieving a clear display with more uniform brightness even when achieving a display with a relatively large area. The waveguide device is capable of achieving display with more uniform brightness while minimizing brightness loss. The invention further discloses application of the waveguide device.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is based on and claims the benefit of priority from Korean Patent Application No. 10-2024-0067554 filed on May 24, 2024 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference. Technical Field

[0003] This specification discloses waveguides and their uses. Background Art

[0004] A waveguide is a channel that causes waves to reflect repeatedly between two interfaces. For example, the principle of such a waveguide is used in optical fibers or liquid crystal displays (LCDs).

[0005] Waveguide devices can also be used to realize virtual reality (VR), augmented reality (AR), mixed reality (MR), or extended reality (XR), etc. For example, Patent Document 1 discloses the application of waveguide devices in realizing virtual reality and the like.

[0006] In the process of realizing virtual reality, light from a light source or display is transmitted through a waveguide device and displayed to an observer.

[0007] When realizing virtual reality, it is important to make the light or display displayed to the viewer have uniform brightness while displaying the highest possible brightness. Patent Document 1 discloses that uniform brightness can be generated by controlling the form of the diffraction grating of a waveguide device.

[0008] Most of the currently known virtual reality implementation technologies, including Patent Document 1, are virtual reality implementation technologies through eyewear devices. That is, the area in which virtual reality is implemented in conventional technologies is relatively narrow.

[0009] On the other hand, for example, technologies such as augmented reality head-up display (AR HUD) that require transmission of light or display over a relatively larger area are being developed, and the demand for more uniform, higher brightness light or display over a wider area is increasing. Summary of the invention

[0010] The present specification discloses a waveguide and its use. The present specification discloses a waveguide device and its use. For example, the present specification discloses a waveguide device for realizing virtual reality (VR), augmented reality (AR), mixed reality (MR), or extended reality (XR), etc. The present specification may disclose a waveguide device that can realize a clear display with more uniform brightness even when the display is realized in a relatively large area. The waveguide device can realize the display with more uniform brightness while minimizing the brightness loss. The present specification also discloses the use of the waveguide device.

[0011] Unless otherwise specified, among the physical properties mentioned in this specification, the physical properties for which the measurement temperature has an impact on the result refer to the results measured at room temperature.

[0012] The term "normal temperature" refers to a temperature in a natural state without heating or cooling, for example, any temperature in the range of 10° C. to 30° C., a temperature of about 23° C. or about 25° C. In addition, unless otherwise specifically defined, the temperature unit in this specification is Celsius (° C.).

[0013] Unless otherwise specified, the physical properties mentioned in this specification for which the measurement pressure has an impact on the result refer to the results measured under normal pressure.

[0014] The term "normal pressure" refers to the pressure in a natural state without being pressurized or reduced, and generally refers to about 740 mmHg to 780 mmHg of standard atmospheric pressure.

[0015] In the physical properties mentioned in this specification, if humidity has an effect on the result, unless otherwise specified, the physical property is the physical property measured under the humidity of the standard state. The humidity of the standard state is a relative humidity, which refers to any degree in the range of 40% to 60%, for example, a relative humidity of about 40% or 60%.

[0016] When an optical characteristic (for example, a refractive index) mentioned in this specification changes according to a wavelength, the optical characteristic refers to a characteristic for light having a wavelength of 633 nm unless otherwise specifically defined.

[0017] This specification discloses a waveguide device.

[0018] The waveguide device may include at least an input diffraction grating pattern, an extended diffraction grating pattern, and an output diffraction grating pattern.

[0019] The term "diffraction grating pattern" is a pattern of a plurality of grooves formed on the surface of a waveguide device, and refers to a pattern formed so as to be able to generate a spectrum or control the path of light by interference between diffracted light in each groove, etc.

[0020] The term "input diffraction grating pattern" refers to a diffraction grating pattern formed to receive all or part of light and / or display and in-coupling the light and / or display into the interior of the waveguide device in a state where the waveguide device is applied.

[0021] The term "extended diffraction grating pattern" refers to a diffraction grating pattern formed to transfer all or part of the light and / or display in-coupling from the input diffraction grating pattern to the output diffraction grating pattern.

[0022] The term "output diffraction grating pattern" refers to a diffraction grating pattern formed to out-coupling all or part of the light transmitted from the extended diffraction grating pattern and / or displayed.

[0023] Figure 1 is an example of the arrangement of the input diffraction grating pattern 1001, the extended diffraction grating pattern 1002 and the output diffraction grating pattern 1003. Figure 1 , light and / or display is coupled into (in-coupling) and transmitted along the path of the dashed arrow, and is coupled out (out-coupling) from the output diffraction grating pattern 1003.

[0024] The waveguide device may be an integrated waveguide device, or may be formed by a plurality of independent waveguide device elements. For example, the input diffraction grating pattern, the extended diffraction grating pattern, and the output diffraction grating pattern may be simultaneously included in one waveguide device, or may be composed of a combination of three waveguide device elements respectively formed with the input diffraction grating pattern, the extended diffraction grating pattern, and the output diffraction grating pattern, or may be composed of a combination of a waveguide device formed with two of the input diffraction grating pattern, the extended diffraction grating pattern, and the output diffraction grating pattern and a waveguide device element formed with the remaining diffraction grating pattern.

[0025] As shown above, the input grating pattern, the extended grating pattern and the output grating pattern can be formed so that external light (including display) is coupled in through the input diffraction grating pattern (in-coupling), and all or part of the coupled-in light passes through the extended diffraction grating pattern and the output diffraction grating pattern in sequence and is coupled out through the output diffraction grating pattern (out-coupling).

[0026] The input diffraction grating pattern, the extended diffraction grating pattern, and the output diffraction grating pattern may each include one diffraction grating region, or two or more diffraction grating regions.

[0027] The term "diffraction grating regions" refers to diffraction grating patterns having substantially the same duty cycle.

[0028] Here, the term “substantially the same duty ratio” is a concept that includes small variations in the duty ratio due to unavoidable errors in the manufacturing process.

[0029] The term "duty ratio" refers to a value obtained by subtracting the width of grooves from the pitch of grooves forming a diffraction grating pattern. In one example, the pitch and width and the height of the grooves may be defined in a cross section of the diffraction grating pattern.

[0030] Figure 2 is an example of a cross section of the diffraction grating pattern. Figure 2 A so-called binary-shaped diffraction grating pattern is schematically shown, but the diffraction grating pattern applicable to the waveguide device is not limited thereto. For example, the diffraction grating pattern may also be a so-called blazed shape, a slanted shape, or other shapes other than the binary shape, or may be a combination of patterns of different shapes.

[0031] In one example, the groove shape in the diffraction grating pattern may be a binary shape or a flame shape.

[0032] Generally, the diffraction efficiency is highest in an inclined shape. However, according to the content disclosed in this specification, even if the shape of the groove is binary or flame-shaped, it is possible to couple out light with excellent efficiency and uniformity.

[0033] like Figure 2 As shown, the pitch P may be the distance from the start of one groove to the start of another groove adjacent to the groove in the diffraction grating pattern.

[0034] like Figure 2 As shown, the width W refers to the size of the groove recognized when the diffraction grating pattern is observed from the top of the diffraction grating pattern, and the width may be the size of the groove confirmed in the same direction as the pitch.

[0035] exist Figure 2 Also shown in FIG. 1 is a height H of the grooves forming the diffraction grating pattern.

[0036] In one example, at least the extended diffraction grating pattern and / or the output diffraction grating pattern among the input diffraction grating pattern, the extended diffraction grating pattern and the output diffraction grating pattern may include a plurality of diffraction grating regions. That is, either the extended diffraction grating pattern or the output diffraction grating pattern may include a plurality of diffraction grating regions, or both may include a plurality of diffraction grating regions.

[0037] For example, in the extended diffraction grating pattern and / or the output diffraction grating pattern including the plurality of diffraction grating regions, ΔD in the following formula 1 may be a negative value in any one or one or more of the plurality of diffraction grating regions.

[0038] [Formula 1]

[0039] △D=100×(D i –D b ) / D b

[0040] In formula 1, D i is the duty cycle of any one of the plurality of diffraction grating regions, and D b The propagation path of the light coupled into the coupling is a duty cycle D i The duty cycle of the grating area through which the light passes before the grating area.

[0041] The meaning of ΔD in Formula 1 is explained with reference to a schematic diagram.

[0042] Figure 3 is Figure 1 In one example, the extended diffraction grating pattern 1002 includes seven diffraction grating regions 10021 to 10027 and the output diffraction grating pattern 1003 includes seven diffraction grating regions 10031 to 10037. As described above, only any one of the extended diffraction grating pattern 1002 and the output diffraction grating pattern 1003 may include a plurality of diffraction grating regions, and if necessary, the input diffraction grating pattern 1001 may also include a plurality of diffraction grating regions.

[0043] As shown, light coupled into the input diffraction grating pattern 1001 is transmitted to the expanded diffraction grating pattern.

[0044] The transmitted light is Figure 3 The light is transmitted from each diffraction grating region to the output diffraction grating pattern while propagating in the direction of the solid arrow at the bottom. The light transmitted to the output diffraction grating pattern is along Figure 3 The leftmost solid arrow direction of is coupled out from each diffraction grating region 10031 to 10037 during propagation within the output diffraction grating pattern.

[0045] In Formula 1, for example, D i refers to the duty ratio of any one of the plurality of diffraction grating regions in a diffraction grating pattern, for example, Figure 3 In the case of, it can be the duty cycle of any one of the diffraction grating regions 10022 to 10027 and / or the duty cycle of any one of the diffraction grating regions 10031 to 10037.

[0046] For example, in Figure 3 In the figure, since there is no diffraction grating region within the diffraction grating region including the diffraction grating region 10021 and 10031 before the light passes through the diffraction grating region along the propagation path of the light, ΔD cannot be defined.

[0047] D in Formula 1 b It means that along the propagation path of the light coupled in, the duty cycle D i In this case, the propagation path of light refers to the direction of light propagation within the diffraction grating pattern including the diffraction grating area. For example, referring to Figure 3 , part of the light transmitted from the input diffraction grating pattern 1001 is transmitted to the output diffraction grating pattern at the diffraction grating region 10021, part of the light is transmitted to the adjacent diffraction grating region 10022, and part of the light propagates in other directions, and the propagation path referred to in Formula 1 refers to the direction from the diffraction grating region 10021 toward the diffraction grating region 10022. Similarly, part of the light transmitted from the extended diffraction grating pattern is coupled out at the diffraction grating region 10031, part of the light is transmitted to the adjacent diffraction grating region 10032, and part of the light propagates in other directions, and the propagation path referred to in Formula 1 refers to the direction from the diffraction grating region 10031 toward the diffraction grating region 10032.

[0048] The negative value of ΔD in Formula 1 means that according to the above content, the duty cycle of the diffraction grating area gradually decreases along the propagation path of light.

[0049] In one example, in the diffraction grating pattern including the plurality of diffraction grating regions, the lower limit of the ratio of the number of all diffraction grating regions that can define the ΔD to the number of diffraction grating regions where the ΔD is negative may be about 30%, 40%, 50%, 60%, 70%, 80%, 90% or 95%, and the upper limit thereof may be about 100%. The ratio may be above or within a range exceeding any one of the above lower limits, or above or within a range exceeding any one of the above lower limits and below or within a range less than any one of the above upper limits. In one example, in the diffraction grating regions in the diffraction grating pattern including the plurality of diffraction grating regions, the ΔD may be negative in all the diffraction grating regions that can define the ΔD.

[0050] When calculating the ΔD, D i and D b The same units apply.

[0051] The lower limit of the absolute value of ΔD may be about 0.1%, 0.5%, 1%, 5%, 10%, 15%, 20%, 25% or 30%, and the upper limit may be about 150%, 100%, 90%, 80%, 70%, 60%, 50%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, 5%, 3% or 1.5%. The absolute value of ΔD may be above or within a range exceeding any of the above lower limits, or below or within a range less than any of the above upper limits, or above or above any of the above lower limits and below or within a range less than any of the above upper limits.

[0052] For example, the diffraction grating pattern including the plurality of diffraction grating regions may be formed to include a diffraction grating region where the absolute value of V in the following formula 2 reaches a certain level or more.

[0053] [Formula 2]

[0054] V = 100 × (AD-△D A ) / S

[0055] In Formula 2, AD is the average (arithmetic mean) of the absolute values ​​of ΔD in Formula 1. That is, AD is the average of the absolute values ​​of ΔD of all diffraction grating regions that can define ΔD in Formula 1 among the diffraction grating regions in the diffraction grating pattern including the plurality of diffraction grating regions.

[0056] In formula 2, △D A is the absolute value of ΔD in equation 1. That is, A is the absolute value of ΔD in equation 1 found in any diffraction grating region.

[0057] S in Formula 2 is the standard deviation of the absolute values ​​of all ΔDs for the plurality of diffraction grating regions. For example, in the diffraction grating pattern included in the diffraction grating pattern, ΔDs obtained in all diffraction grating regions where ΔD can be defined are D1, D2, D3, and D4, and the average of the absolute value of D1, the absolute value of D2, the absolute value of D3, and the absolute value of D4 is A, then S is obtained by [{(absolute value of A-D1)2+(absolute value of A-D2)2+(absolute value of A-D3)2+(absolute value of A-D4)2} / 4] 0.5 The value found.

[0058] For example, a region where the absolute value of V in Formula 2 reaches above a certain level among multiple diffraction grating regions within the diffraction grating pattern can be called region A, and a region where the absolute value of V in Formula 2 is below a certain level can be called region B.

[0059] The lower limit of the absolute value of V in the region A may be about 100%, 130%, 150%, 170%, 190%, 200%, 250%, 300%, 320% or 340%, and the upper limit thereof may be about 1000%, 900%, 800%, 700%, 600%, 500%, 400%, 350%, 300%, 250% or 200%. The absolute value of V in the region A may be above or within a range exceeding any of the above lower limits, or above or within a range exceeding any of the above lower limits and below or within a range less than any of the above upper limits.

[0060] The lower limit of the absolute value of V in the region B may be about 1%, 3%, 4%, 5%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80% or 90%, and the upper limit thereof may be about 100%, 95%, 90%, 80%, 70%, 60%, 50%, 40%, 30%, 20%, 10% or 5%. The absolute value of V in the region B may be in a range below or not exceeding any of the above upper limits, or in a range above or exceeding any of the above lower limits and below or less than any of the above upper limits.

[0061] In regions A and B, the absolute values ​​of V are different from each other.

[0062] The V can be negative or positive.

[0063] In one example, V in the region A may be a negative value, and V in the region B may be a positive value or a negative value.

[0064] Reference Figure 3 , V in Formula 2 refers to the duty cycle of the diffraction grating region included in the diffraction grating pattern along the propagation path of light ( Figure 3 When the solid arrow direction in the diffraction grating pattern changes, how does the degree of change change compared to the standard deviation of the degree of change of all diffraction grating areas?

[0065] That is, the larger V is, the greater the value is, indicating that the diffraction grating region of V changes at a larger duty cycle compared to the average degree of change of other diffraction grating regions.

[0066] Reference Figure 3 Since the input diffraction grating pattern 1001 is closest to the light source, when the output diffraction grating pattern corresponds to the displayed picture, under the same other conditions, it can be expected that the brightness at the lower right end of the output diffraction grating pattern is the brightest, while the brightness at the upper left end is the lowest.

[0067] Therefore, in order to make the screen brightness uniform, it is necessary to gradually increase the amount of light transmitted to the output diffraction grating pattern from the diffraction grating area 10021 to the diffraction grating area 10027, and gradually increase the amount of coupled-out light from the diffraction grating area 10031 to the diffraction grating area 10037.

[0068] In addition, it can be expected that making the amount of light transmitted to the output diffraction grating pattern constant as the amount (increase amplitude) gradually increases from the diffraction grating region 10021 to the diffraction grating region 10027, and making the amount of coupled out light constant as the amount (increase amplitude) gradually increases from the diffraction grating region 10031 to the diffraction grating region 10037 will be beneficial to achieving uniform brightness.

[0069] In general, the amount of light diffracted from a diffraction grating region and transmitted to other regions or coupled out is related to the duty cycle of the diffraction grating region. Figure 3 In the example, theoretically, decreasing the duty cycle of the region at a uniform ratio from the diffraction grating region 10021 to the diffraction grating region 10027 and decreasing the duty cycle of the region at a uniform ratio from the diffraction grating region 10031 to the diffraction grating region 10037 will be beneficial to achieving uniform brightness.

[0070] However, it turns out that when there is a region (i.e., region A) among multiple diffraction grating regions in which the duty cycle variation of at least part of the region is greater or smaller than the average variation among the multiple diffraction grating regions, it is unexpectedly beneficial to effectively achieve the uniform brightness while minimizing the reduction in brightness.

[0071] In particular, when AD of Formula 2 is within the following range and / or S of Formula 2 is within the following range and the region A exists, the improvement effect of the uniformity and / or the improvement effect of the efficiency can be further enhanced.

[0072] Therefore, in the waveguide device disclosed in the present specification, for example, the diffraction grating pattern including the multiple diffraction grating regions (for example, the extended diffraction grating pattern and / or the output diffraction grating pattern) can be designed to include the region A where the absolute value of V in Formula 2 reaches above a certain level.

[0073] The range of the average (arithmetic mean) of the absolute values ​​of ΔD in Formula 1, i.e., AD in Formula 2, is not particularly limited. For example, the lower limit of the AD may be about 7, 7.5, 8, 8.5, or 9, and the upper limit thereof may be about 100, 80, 60, 40, 20, 15, 10, 9, or 8. The AD may be above or in a range exceeding any of the lower limits, or below or in a range less than any of the upper limits, or above or in a range exceeding any of the lower limits and below or in a range less than any of the upper limits. The unit of the AD is percentage (%).

[0074] For example, in the case where both the output diffraction grating pattern and the extended diffraction grating pattern include a plurality of diffraction grating regions, AD in each of the diffraction grating patterns may be the same as or different from each other within the above range.

[0075] S in Formula 2, i.e., the standard deviation of the absolute values ​​of all ΔDs for the plurality of diffraction grating regions, is not particularly limited. For example, the lower limit of S may be about 6, 6.5, 7, 7.5, 8, 9, 10, or 11, and the upper limit thereof may be about 100, 80, 60, 40, 20, 15, 10, 9, or 8. S may be above or within a range exceeding any of the above lower limits, or below or within a range less than any of the above upper limits, or above or exceeding any of the above lower limits and below or within a range less than any of the above upper limits. The unit of S may be percentage (%).

[0076] For example, in the case where both the output diffraction grating pattern and the extended diffraction grating pattern include a plurality of diffraction grating regions, S in each of the diffraction grating patterns may be the same as or different from each other within the above range.

[0077] In the case where a diffraction grating pattern (e.g., an output diffraction grating pattern and / or an extended diffraction grating pattern) includes a plurality of diffraction grating regions, the ratio of the region A in the diffraction grating region defining the V among all the diffraction grating regions of the diffraction grating pattern including the plurality of diffraction grating regions may be about 1%, 5%, 10% or 15%, and the upper limit thereof may be about 45%, 40%, 35%, 30%, 25% or 20%. The ratio may be above or within a range exceeding any of the above lower limits, or below or within a range less than any of the above upper limits, or above or above any of the above lower limits and below or within a range less than any of the above upper limits. If the ratio of the region A is too high, the efficiency and / or uniformity of the light coupled out may decrease, and thus the ratio of the region A may be adjusted within a range not too high.

[0078] A region other than the region A among the plurality of diffraction grating regions may be a region B.

[0079] In the case where the diffraction grating pattern includes a plurality of diffraction grating regions, the number of diffraction grating regions included in one diffraction grating pattern is not particularly limited. For example, the lower limit of the number of the diffraction grating regions may be about 4, 5, 6, or 7, and the upper limit thereof may be about 100, 80, 60, 40, 20, 15, or 10. The number of the diffraction grating regions may be above or in a range exceeding any of the above lower limits, or below or in a range less than any of the above upper limits, or above or in a range exceeding any of the above lower limits and below or in a range less than any of the above upper limits.

[0080] The duty ratio of each of the input diffraction grating pattern, the extended diffraction grating pattern, and the output diffraction grating pattern can be set within an appropriate range according to the purpose. For example, the lower limit of the duty ratio can be about 50nm, 100nm, 150nm, 200nm, 250nm, 300nm, or 350nm, and the upper limit thereof can be about 1000nm, 900nm, 800nm, 700nm, 600nm, 500nm, 400nm, 350nm, 300nm, 250nm, 200nm, 180nm, or 160nm. The duty ratio can be above or within a range exceeding any of the above lower limits, or below or within a range less than any of the above upper limits, or above or within a range exceeding any of the above lower limits and below or within a range less than any of the above upper limits.

[0081] In the case that the input diffraction grating pattern, the extended diffraction grating pattern and / or the output diffraction grating pattern includes a plurality of diffraction grating regions, the duty cycle is an average value of the duty cycles of the plurality of diffraction grating regions.

[0082] The duty ratio of each of the input diffraction grating pattern, the extended diffraction grating pattern, and the output diffraction grating pattern may be the same as or different from each other within the above range. For example, in the case where the duty ratios of each of the input diffraction grating pattern, the extended diffraction grating pattern, and the output diffraction grating pattern are different from each other, the duty ratio of the output diffraction grating pattern may have a maximum value, and the duty ratio of the extended diffraction grating pattern may have a minimum value.

[0083] The pitch of each of the input diffraction grating pattern, the extended diffraction grating pattern, and the output diffraction grating pattern can be set within an appropriate range according to the purpose. For example, the lower limit of the pitch can be about 50nm, 100nm, 150nm, 200nm, 250nm, 300nm, 350nm, 400nm, 450nm, or 500nm, and the upper limit thereof can be about 2000nm, 1500nm, 1000nm, 900nm, 800nm, 700nm, 600nm, 500nm, or 400nm. The pitch can be above or within a range exceeding any of the above lower limits, or below or within a range less than any of the above upper limits, or above or within a range exceeding any of the above lower limits and below or within a range less than any of the above upper limits.

[0084] In the case where the input diffraction grating pattern, the extended diffraction grating pattern and / or the output diffraction grating pattern include a plurality of diffraction grating regions, the pitch is an average of the pitches of the plurality of diffraction grating regions. In one example, in the case where the diffraction grating pattern includes a plurality of diffraction grating regions, the pitch of each of the diffraction grating regions may be substantially the same as each other.

[0085] The pitch of each of the input diffraction grating pattern, the extended diffraction grating pattern, and the output diffraction grating pattern may be the same as or different from each other within the above range. For example, in the case where the pitch of each of the input diffraction grating pattern, the extended diffraction grating pattern, and the output diffraction grating pattern is different from each other, the pitch of the extended diffraction grating pattern may have a minimum value. In this case, the pitch of the input diffraction grating pattern and the extended diffraction grating pattern may be the same as or different from each other.

[0086] The height (eg, Figure 2 The height (H) can be set in a suitable range according to purpose. For example, the lower limit of the height can be about 10nm, 50nm, 100nm, 150nm or 200nm, and its upper limit can be about 1000nm, 900nm, 800nm, 700nm, 600nm, 500nm, 400nm, 300nm or 250nm. The height can be above any lower limit in the above-mentioned lower limit or exceed its scope, or below any upper limit in the above-mentioned upper limit or be insufficient in its scope, or above any lower limit in the above-mentioned lower limit or exceed it and below any upper limit in the above-mentioned upper limit or be insufficient in its scope.

[0087] The height of the input diffraction grating pattern, the extended diffraction grating pattern and / or the output diffraction grating pattern is the average value of these heights when the respective patterns contain parts with different heights. In one example, the height of the grooves in the diffraction grating pattern may be substantially constant or may not be constant.

[0088] In one example, at least the extended diffraction grating pattern and the output diffraction grating pattern among the input diffraction grating pattern, the extended diffraction grating pattern and the output diffraction grating pattern may include a plurality of diffraction grating regions each distinguished by a duty cycle, and in this case, the extended diffraction grating pattern may also include at least one of the regions A, and the output diffraction grating pattern may also include at least one of the regions A.

[0089] In this case, the lower limit of the ratio of the region A in all the diffraction grating regions defining the V in each of the output diffraction grating pattern and the extended diffraction grating pattern may be about 1%, 5%, 10%, or 15%, and the upper limit thereof may be about 45%, 40%, 35%, 30%, 25%, or 20%. The ratio may be above or in a range exceeding any of the above lower limits, or below or in a range less than any of the above upper limits, or above or in a range exceeding any of the above lower limits and below or in a range less than any of the above upper limits.

[0090] When the extended diffraction grating pattern includes a plurality of diffraction grating regions, at least the last diffraction grating region may be the region A. In this case, the last diffraction grating region refers to the diffraction grating region that the light passes through last along the propagation path of the light among the diffraction grating regions present in the extended diffraction grating pattern, for example, Figure 3 Diffraction grating region 10027.

[0091] When the output diffraction grating pattern includes a plurality of diffraction grating regions, at least the last diffraction grating region may be the region A. In this case, the last diffraction grating region refers to the diffraction grating region that the light passes through last along the propagation path of the light among the diffraction grating regions present in the output diffraction grating pattern, for example, Figure 3 Diffraction grating region 10037.

[0092] In the waveguide device, a first direction (for example, in Figure 3 In the case of the case of the bottom solid arrow direction in the figure) and the second direction composed of a plurality of diffraction grating regions of the output diffraction grating pattern (for example, in Figure 3 In the case of, the angle between the leftmost solid arrow direction in the figure). For example, the lower limit of the smaller angle among the angles formed by the first direction and the second direction may be about 70 degrees, 75 degrees, 80 degrees, 85 degrees or 90 degrees, and the upper limit thereof may be about 110 degrees, 105 degrees, 100 degrees, 95 degrees or 90 degrees. The angle may be above or within a range exceeding any of the lower limits mentioned above, or below or within a range less than any of the upper limits mentioned above, or above or exceeding any of the lower limits mentioned above and below or within a range less than any of the upper limits mentioned above.

[0093] In one example, the angle may be approximately 90 degrees.

[0094] In the waveguide device, an average value De of the duty cycle of the extended diffraction grating pattern and an average value Do of the duty cycle of the output diffraction grating pattern may satisfy a predetermined relationship.

[0095] For example, the Do may be greater than De.

[0096] In this case, ΔD2 of the following Formula 4 may be within a predetermined range.

[0097] [Formula 4]

[0098] △D2=100×(Do–De) / De

[0099] In Equation 4, De is the average value of the duty cycle of the extended diffraction grating pattern, and Do is the average value of the duty cycle of the output diffraction grating pattern.

[0100] The lower limit of ΔD2 of Formula 4 may be about 50%, 70%, 90%, 110%, 130%, 140% or 145%, and the upper limit thereof may be about 1000%, 900%, 800%, 700%, 600%, 500%, 400%, 300%, 200%, 180%, 160% or 150%. The ΔD2 may be above or in a range exceeding any of the above lower limits, or below or in a range less than any of the above upper limits, or above or in a range exceeding any of the above lower limits and below or in a range less than any of the above upper limits.

[0101] In the waveguide device, the pitch of the extended diffraction grating pattern (the average value of the pitch when the pitches of multiple diffraction grating regions are different from each other) Pe and the pitch of the output diffraction grating pattern (the average value of the pitch when the pitches of multiple diffraction grating regions are different from each other) Po can satisfy a predetermined relationship.

[0102] For example, the Po may be greater than the Pe.

[0103] In this case, ΔP1 of the following Formula 6 may be within a predetermined range.

[0104] [Formula 6]

[0105] △P1=100×(Po–Pe) / Pe

[0106] In Formula 6, Pe is the pitch of the extended diffraction grating pattern (the average value of the pitches when the pitches of multiple diffraction grating regions are different from each other), and Po is the pitch of the output diffraction grating pattern (the average value of the pitches when the pitches of multiple diffraction grating regions are different from each other).

[0107] The lower limit of ΔP1 in Formula 6 may be about 5%, 10%, 15%, 20%, 25%, 30%, 35% or 40%, and the upper limit thereof may be about 500%, 400%, 300%, 200%, 100%, 90%, 80%, 70%, 60%, 50% or 45%. The ΔP1 may be above or in a range exceeding any of the above lower limits, or below or in a range less than any of the above upper limits, or above or in a range exceeding any of the above lower limits and below or in a range less than any of the above upper limits.

[0108] To achieve the purpose, the design of the waveguide device can be further adjusted.

[0109] For example, the waveguide device may be designed such that ΔD3 of the following equation 7 is within a predetermined range.

[0110] [Formula 7]

[0111] △D3=100×(D of –D el ) / D el .

[0112] In formula 7, D el is the diffraction grating area of ​​the extended diffraction grating pattern that the light coupled into the waveguide device finally passes through along the propagation path of the light (for example, in Figure 3 In the case of the diffraction grating area 10027), the duty cycle, and D of is a diffraction grating region (for example, in Figure 3 In the case of , the duty cycle of the diffraction grating area 10031).

[0113] The lower limit of ΔD3 of Formula 7 may be about 100%, 150%, 200%, 250% or 300%, and the upper limit thereof may be about 1500%, 1000%, 900%, 800%, 700%, 600%, 500%, 400% or 350%. The ΔD3 may be above or in a range exceeding any of the above lower limits, or below or in a range less than any of the above upper limits, or above or in a range exceeding any of the above lower limits and below or in a range less than any of the above upper limits.

[0114] In the waveguide device, the duty cycle of the input diffraction grating pattern (the average of the duty cycles of the multiple diffraction grating regions when multiple diffraction grating regions are included) Din and the duty cycle of the extended diffraction grating pattern (the average of the duty cycles of the multiple diffraction grating regions when multiple diffraction grating regions are included) De can satisfy a predetermined relationship.

[0115] For example, the Din may be greater than the De.

[0116] In this case, ΔD4 of the following Formula 9 may be within a predetermined range.

[0117] [Formula 9]

[0118] △D4=100×(Din–De) / De

[0119] In Formula 9, Din is the duty cycle of the input diffraction grating pattern (in the case of including multiple diffraction grating regions, the average of the duty cycles of the multiple diffraction grating regions), and De is the duty cycle of the extended diffraction grating pattern (in the case of including multiple diffraction grating regions, the average of the duty cycles of the multiple diffraction grating regions).

[0120] The lower limit of D4 in Formula 9 may be about 5%, 10%, 15%, 20%, 25%, 30%, 35% or 40%, and the upper limit thereof may be about 500%, 400%, 300%, 200%, 100%, 90%, 80%, 70%, 60%, 50% or 45%. The ΔD4 may be above or in a range exceeding any of the above lower limits, or below or in a range less than any of the above upper limits, or above or in a range exceeding any of the above lower limits and below or in a range less than any of the above upper limits.

[0121] In addition, the pitch of the input diffraction grating pattern (the average of the pitches of the multiple diffraction grating areas when multiple diffraction grating areas are included) Pin and the pitch of the extended diffraction grating pattern (the average of the pitches of the multiple diffraction grating areas when multiple diffraction grating areas are included) Pe can satisfy a predetermined relationship.

[0122] For example, the Pin may have a greater value than the Pe.

[0123] In this case, ΔP2 of the following equation 11 may be within a predetermined range.

[0124] [Formula 11]

[0125] △P2=100×(Pin–Pe) / Pe

[0126] In Formula 11, Pin is the pitch of the input diffraction grating pattern (in the case of including multiple diffraction grating regions, the average of the pitches of the multiple diffraction grating regions), and Pe is the pitch of the extended diffraction grating pattern (in the case of including multiple diffraction grating regions, the average of the pitches of the multiple diffraction grating regions).

[0127] The lower limit of ΔP2 of Formula 11 may be about 5%, 10%, 15%, 20%, 25%, 30%, 35% or 40%, and the upper limit thereof may be about 500%, 400%, 300%, 200%, 100%, 90%, 80%, 70%, 60%, 50% or 45%. The ΔP2 may be above or in a range exceeding any of the above lower limits, or below or in a range less than any of the above upper limits, or above or in a range exceeding any of the above lower limits and below or in a range less than any of the above upper limits.

[0128] The waveguide device may also be designed so that ΔD5 of the following equation 12 is within a predetermined range.

[0129] [Formula 12]

[0130] △D5=100×(D if –D ef ) / D el

[0131] In formula 12, D if is the duty cycle of the input diffraction grating pattern (the average of the duty cycles in the case of multiple diffraction grating regions), and D ef is the diffraction grating region of the extended diffraction grating pattern that the light first passes through along the propagation path of the light coupled into the waveguide device (for example, in Figure 3 In the case of , the duty cycle of the diffraction grating area 10021).

[0132] The lower limit of ΔD5 of Formula 12 may be about 1%, 5%, 10%, 15% or 20%, and the upper limit thereof may be about 500%, 400%, 300%, 200%, 100%, 90%, 80%, 70%, 60%, 50%, 40%, 30% or 25%. The ΔD5 may be above or in a range exceeding any of the above lower limits, or below or in a range less than any of the above upper limits, or above or in a range exceeding any of the above lower limits and below or in a range less than any of the above upper limits.

[0133] The waveguide device can be manufactured in a conventional manner using known materials for forming the waveguide device. That is, when the waveguide device disclosed in this specification is formed with a diffraction grating pattern according to the above design, its materials and manufacturing method can follow a known manner.

[0134] For example, the waveguide device may have a refractive index exhibited by a material of a conventional waveguide device. For example, the lower limit of the refractive index of the waveguide device may be about 1.40, 1.45, 1.50, 1.55, or 1.60, and the upper limit thereof may be about 1.80, 1.75, 1.70, 1.65, or 1.60. The refractive index is a value based on a wavelength of 633 nm. The refractive index may be above or within a range exceeding any of the above lower limits, or below or within a range less than any of the above upper limits, or above or above any of the above lower limits and below or within a range less than any of the above upper limits.

[0135] Waveguide devices are generally manufactured by so-called imprinting (i.e., a method of replicating a diffraction grating pattern of a desired shape using a predetermined mold) or etching technology (i.e., a method of cutting out material to have a desired diffraction grating pattern), and the waveguide device disclosed in this specification can be manufactured by the known methods as described above.

[0136] The size of the diffraction grating pattern or the size of the diffraction grating area when the diffraction grating pattern includes a plurality of diffraction grating areas can be adjusted to an appropriate level as needed. In this case, the size is a size measured along the propagation path of light in the waveguide device, for example, Figure 3 In the example, the size of the diffraction grating pattern 1001 is expressed as W. in Indicated, the sizes of the diffraction grating regions 10021 to 10027 of the extended diffraction grating pattern are denoted by W1 to W7, and the sizes of the diffraction grating regions 10031 to 10037 of the output diffraction grating pattern are denoted by L1 to L7.

[0137] The lower limit of the size may be about 1 mm, 3 mm, 5 mm, 7 mm, 9 mm or 11 mm, and the upper limit thereof may be about 100 mm, 90 mm, 80 mm, 70 mm, 60 mm, 50 mm, 40 mm, 30 mm, 20 mm, 15 mm or 10 mm. The size may be above or within a range exceeding any of the lower limits, or below or within a range less than any of the upper limits, or above or above any of the lower limits and below or within a range less than any of the upper limits.

[0138] The sizes of the corresponding diffraction grating patterns or diffraction grating regions may be the same as or different from each other within the above range.

[0139] In one example, when a diffraction grating pattern includes a plurality of diffraction grating regions, the sizes of the plurality of diffraction grating regions within the diffraction grating pattern may be substantially the same as each other. In this case, the substantially same size means that the standard deviation of the size is below a certain level. For example, the upper limit of the standard deviation of the substantially same size may be about 5 mm, 4 mm, 3 mm, 2 mm, 1 mm or 0.5 mm, and the lower limit thereof may be about 0 mm. The standard deviation may be within a range below or not exceeding any of the above upper limits, or within a range above or exceeding any of the above lower limits and below or less than any of the above upper limits.

[0140] The ratio of the size of the diffraction grating pattern or the diffraction grating area to the size in the direction perpendicular thereto may also be adjusted to an appropriate level as required. In this case, the ratio is the ratio of the size measured along the light propagation path in the waveguide device to the size measured in the direction perpendicular to the light propagation path, for example, referring to Figure 3 , the ratio of the diffraction grating region 10037 is W / L7, the ratio of the diffraction grating region 10027 is L / W7, and the ratio of the input diffraction grating pattern 1001 is L in / W in .

[0141] The lower limit of the ratio may be about 0.1, 0.5, 1, 3, 5, 7, 9 or 11, and the upper limit thereof may be about 100, 90, 80, 70, 60, 50, 40, 30, 20, 15, 10, 8, 6, 4, 2 or 1. The ratio may be above or in a range exceeding any of the above lower limits, or below or in a range less than any of the above upper limits, or above or in a range exceeding any of the above lower limits and below or in a range less than any of the above upper limits.

[0142] The ratios in the corresponding diffraction grating patterns or diffraction grating regions may be the same as or different from each other within the above range.

[0143] Through the design, the waveguide device can couple out light to have uniform brightness.

[0144] For example, the lower limit of the uniformity of all polarized lights coupled out from the waveguide device may be about 75%, 77%, 79% or 80%, and the upper limit thereof may be about 100%, 95%, 90% or 85%. The ratio may be above or in a range exceeding any of the above lower limits, or above or in a range exceeding any of the above lower limits and below or in a range less than any of the above upper limits. The uniformity is confirmed by the method described in "Test Example 1" of the Example item of this specification.

[0145] The waveguide device can perform light coupling out with excellent efficiency and excellent uniformity. For example, the lower limit of the efficiency of all polarized lights coupled out from the waveguide device can be about 1%, 2%, 3%, 4%, 5% or 5.5%, and the upper limit thereof can be about 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, 9%, 8%, 7% or 6%. The efficiency can be above or within a range exceeding any of the above lower limits, or above or within a range exceeding any of the above lower limits and below or within a range less than any of the above upper limits. The efficiency is confirmed by the method described in "Test Example 1" of the embodiment item of this specification.

[0146] When the uniformity and efficiency of the outcoupled light are viewed from the perspective of S-polarized light, the performance of the waveguide device is further improved.

[0147] For example, the lower limit of the uniformity of all S-polarized light coupled out from the waveguide device may be about 80%, 81%, 82%, 83%, 84% or 85%, and the upper limit thereof may be about 100%, 95%, 90% or 85%. The ratio may be above or in a range exceeding any of the above lower limits, or above or in a range exceeding any of the above lower limits and below or in a range less than any of the above upper limits. The uniformity is confirmed by the method described in "Test Example 1" of the Example item of this specification.

[0148] For example, the lower limit of the efficiency of all S-polarized light coupled out from the waveguide device may be about 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, or 8.5%, and the upper limit thereof may be about 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, or 9%. The efficiency may be above or in a range exceeding any of the above lower limits, or above or in a range exceeding any of the above lower limits and below or in a range less than any of the above upper limits. The efficiency is confirmed by the method described in "Test Example 1" of the Example item of this specification.

[0149] According to the design of the waveguide device, even if the area of ​​the waveguide device (i.e., the coupling output area or the light output area) is large, the above-mentioned excellent uniformity and / or efficiency can be ensured. For example, the lower limit of the light output area of ​​the waveguide device may be 30 cm 2 、35cm 2 、40cm 2 or 45cm 2 About, and its upper limit can be 500cm 2、450cm 2 、400cm 2 、350cm 2 、300cm 2 、250cm 2 , 200cm 2 、150cm 2 , 100cm 2 、90cm 2 、80cm 2 、70cm 2 、60cm 2 or 50cm 2 The light exit area may be above or within a range exceeding any of the above lower limits, or above or within a range exceeding any of the above lower limits and below or within a range less than any of the above upper limits.

[0150] This specification also discloses the use of the waveguide device.

[0151] For example, this specification discloses an extended reality device including the waveguide device.

[0152] Examples of extended reality devices include virtual reality (VR) devices, augmented reality (AR) devices, mixed reality (MR) devices, or extended reality (XR) devices, among others.

[0153] The manner of applying the waveguide device to constitute the extended reality device is not particularly limited, and the device can be implemented in a known manner as long as the waveguide device disclosed in this specification is applied.

[0154] For example, this specification also discloses a head-up display (Head-Up Display) device including the waveguide device.

[0155] The head-up display device may be a so-called augmented reality (AR) head-up display device.

[0156] The manner of using the waveguide device to form the head-up display (HUD) device is not particularly limited. As long as the waveguide device disclosed in this specification is used, the device can be implemented in a known manner.

[0157] The present specification discloses waveguides and their uses. For example, the present specification discloses waveguide devices for realizing virtual reality (VR), augmented reality (AR), mixed reality (MR), or extended reality (XR), etc. The present specification may disclose waveguide devices that can realize clear display with more uniform brightness even when display is realized over a relatively large area. The waveguide device can realize display with more uniform brightness while minimizing brightness loss. The present specification also discloses uses of the waveguide device. BRIEF DESCRIPTION OF THE DRAWINGS

[0158] Figure 1 is one example of the arrangement of the input diffraction grating pattern, the expanded diffraction grating pattern, and the output diffraction grating pattern.

[0159] Figure 2 is an example of a cross section of a diffraction grating pattern.

[0160] Figure 3 is one example of the arrangement of the input diffraction grating pattern, the expanded diffraction grating pattern, and the output diffraction grating pattern.

[0161] Figure 4 1 is a diagram showing the evaluation results of the uniformity and efficiency of the waveguide device of Example 1.

[0162] Figure 5 1 is a diagram showing the evaluation results of the uniformity and efficiency of the waveguide device of Example 1.

[0163] Figure 6 3 is a graph showing the evaluation results of the uniformity and efficiency of the waveguide device of Comparative Example 1.

[0164] Figure 7 3 is a graph showing the evaluation results of the uniformity and efficiency of the waveguide device of Comparative Example 1. DETAILED DESCRIPTION

[0165] The waveguide device and the like are described in detail below through embodiments and comparative examples, but the scope of the waveguide device is not limited to the embodiments described below.

[0166] Example 1.

[0167] The waveguide device was realized using a conventional material for realizing a waveguide device (acrylic material having a refractive index of about 1.60 for light of a wavelength of 633 nm).

[0168] like Figure 3As shown in , the waveguide device includes an input diffraction grating pattern 1001, an extended diffraction grating pattern and an output diffraction grating pattern, the extended diffraction grating pattern includes 7 diffraction grating regions 10021 to 10027, and the output diffraction grating pattern includes 7 diffraction grating regions 10031 to 10037.

[0169] The waveguide device is manufactured so that Figure 3 L1 to L7 are about 7mm, W are about 100mm, W1 to W7 and W in are about 12mm respectively, and L and L in They are about 10mm respectively.

[0170] The grooves of the respective diffraction grating regions 10021 to 10027 and 10031 to 10037 and the input diffraction grating pattern 1001 are as follows: Figure 2 The binary form shown in , and at this time, the pitch P, width W, duty ratio and height H of the binary form become the forms shown in the following Table 1. In the following Table 1, DC is the duty ratio.

[0171] In the following Table 1, ΔD of Formula 1 and V of Formula 2 are also shown.

[0172] In the following Table 1, the units of width, pitch, height and duty ratio are nm, and the units of ΔD and V are %.

[0173] [Table 1]

[0174]

[0175]

[0176] Comparative Example 1.

[0177] A waveguide device was manufactured in the same manner as in Example 1, except that the pitch P, width W, duty ratio and height H of the grooves of the binary form of each diffraction grating region 10021 to 10027 and 10031 to 10037 and the input diffraction grating pattern 1001 were adjusted as shown in Table 2 below.

[0178] In Table 2 below, DC is the duty cycle.

[0179] In the following Table 2, ΔD of Formula 1 and V of Formula 2 are also shown together.

[0180] In Table 2 below, the units of width, pitch, height, and duty ratio are nm, and the units of ΔD and V are %.

[0181] [Table 2]

[0182]

[0183] Test example 1.

[0184] The efficiency and uniformity of the waveguide device were evaluated in the following manner.

[0185] A light source was used to irradiate light to the input diffraction grating pattern 1001 of the waveguide device of Example 1 and Comparative Example 1. The light was irradiated at 300 mW / cm 2 The amount of irradiation is about 532nm wavelength of unpolarized light.

[0186] Next, the amount and brightness of light coupled out from the output diffraction grating pattern of the waveguide device were evaluated.

[0187] Wherein, the light quantity is measured as the light quantity of the entire coupling-out region, and the brightness is as follows Figures 4 to 7 The coupling output region formed by the waveguide device shown in the figure was divided into 49 regions of equal area and then evaluated in each region.

[0188] The light quantity and the brightness were evaluated using a photodiode power sensor (S121C) from Thorlabs.

[0189] Next, the efficiency is calculated according to the following formula A, and the uniformity is calculated according to the following formula B.

[0190] [Formula A]

[0191] Efficiency (%) = 100 × L out / L in

[0192] In formula A, L in is the amount of light irradiated from the light source, L out is the amount of light coupled out from the outcoupling region, and L in and L out The units are the same as each other.

[0193] When calculating the efficiency for all polarized lights in Table 3 below, the amount of light emitted from the light source is substituted into the L in , and the amount of all light coupled out from the coupling-out region is substituted into L out .

[0194] When calculating the efficiency for S-polarized light in Table 3 below, the amount of S-polarized light in the light irradiated from the light source is substituted into the L in , and the amount of S-polarized light in the light coupled out from the coupling-out region is substituted into L out .

[0195] [Formula B]

[0196] Uniformity (%) = 100 × B min / B max

[0197] In formula B, B min is the lowest brightness among the brightnesses measured in the 49 regions of the same area, B max is the highest brightness among the brightnesses respectively measured in the 49 regions of the same area, and B min and B max The units are the same as each other.

[0198] When calculating the uniformity of all polarized lights in Table 3 below, the brightness for all polarized lights is substituted into the B min and the B max , and when calculating the uniformity for S polarized light, the brightness for S polarized light is substituted into the B min and the B max .

[0199] [Table 3]

[0200]

[0201]

[0202] From the results in Table 3, it can be confirmed that the waveguide device of Example 1 exhibits more excellent efficiency and higher uniformity than those of Comparative Example 1, and it can be confirmed from the perspective of S-polarized light that the characteristics are further improved.

Claims

1. A waveguide device comprising an input diffraction grating pattern, an extended diffraction grating pattern and an output diffraction grating pattern, The grating pattern is formed so that external light is coupled in through the input diffraction grating pattern, and the coupled-in light sequentially passes through the extended diffraction grating pattern and the output diffraction grating pattern and is coupled out by the output diffraction grating pattern, One or both of the extended diffraction grating pattern and the output diffraction grating pattern respectively include a plurality of diffraction grating regions differentiated by a duty cycle, The △D in the following formula 1 is a negative value. In one or more of the plurality of diffraction grating regions, the absolute value of V of the following Formula 2 is 100% or more, AD of the following formula 2 is 7% or more, or S of the following formula 2 is 6% or more, [Formula 1] △D=100×(D i –D b ) / D b , In Formula 1, D i is the duty cycle of any one of the plurality of diffraction grating regions, and D b is the propagation path of the light coupled in, with the duty cycle D i The duty ratio of the grating area that the light passes through before the grating area, [Formula 2] V=100×(AD-△D A ) / S, In the formula 2, AD is the average value of the absolute value of ΔD in the formula 1, ΔD A is the absolute value of the ΔD of the formula 1, and S is the standard deviation of the absolute values ​​of all the ΔDs for the plurality of diffraction grating regions.

2. The waveguide device according to claim 1, wherein: The uniformity of the outcoupled light is 75% or higher.

3. The waveguide device according to claim 1, wherein: The uniformity of the outcoupled S-polarized light is 80% or higher.

4. The waveguide device according to claim 1, wherein: An absolute value of the V in the formula 2 is 100% or more in 1% to 45% of the diffraction grating regions in the grating pattern including the plurality of diffraction grating regions.

5. The waveguide device according to claim 1, wherein: The grating pattern including the plurality of diffraction grating regions includes 4 or more of the diffraction grating regions.

6. The waveguide device according to claim 1, wherein: An average value of a duty cycle of the grating pattern including the plurality of diffraction grating regions is in a range of 50 nm to 1000 nm.

7. The waveguide device according to claim 1, wherein: A pitch of the grating pattern including the plurality of diffraction grating regions is in the range of 100 nm to 2000 nm.

8. The waveguide device according to claim 1, wherein: The extended diffraction grating pattern and the output diffraction grating pattern respectively include the plurality of diffraction grating regions differentiated by duty ratio, In one or more of the plurality of diffraction grating regions of the extended diffraction grating pattern, the absolute value of the V of the formula 2 is 100% or more, and In one or more diffraction grating areas among a plurality of diffraction grating areas of the output diffraction grating pattern, an absolute value of the V of the formula 2 is 100% or more.

9. The waveguide device according to claim 8, wherein: The absolute value of the V in the last diffraction grating region of the plurality of diffraction grating regions of the extended diffraction grating pattern is 100% or more.

10. The waveguide device according to claim 8, wherein: The absolute value of the V in the last diffraction grating region of the plurality of diffraction grating regions of the output diffraction grating pattern is 100% or more.

11. The waveguide device according to claim 8, wherein: A smaller angle among angles formed by a first direction formed by the plurality of diffraction grating regions of the extended diffraction grating pattern and a second direction formed by the plurality of diffraction grating regions of the output diffraction grating pattern is in a range of 70 to 110 degrees.

12. The waveguide device according to claim 8, wherein: The average value D of the duty cycle of the extended diffraction grating pattern e and the average value D of the duty cycle of the output diffraction grating pattern o Satisfies the following formula 3, The ΔD2 of the following formula 4 is 50% or more, [Formula 3] D o >D e , [Formula 4] △D2=100×(D o –D e ) / D e 。 13. The waveguide device according to claim 8, wherein: The pitch P of the extended diffraction grating pattern e and the pitch P of the output diffraction grating pattern o Satisfies the following formula 5, The ΔP1 of the following formula 6 is 5% or more: [Formula 5] P o >P e , [Formula 6] △P1=100×(P o –P e ) / P e 。 14. The waveguide device according to claim 8, wherein: The ΔD3 of the following formula 7 is 100% or more: [Formula 7] △D3=100×(D of –D el ) / D el , In formula 7, D el is the duty ratio of the diffraction grating region that the light finally passes through in the extended diffraction grating pattern along the propagation path of the light coupled into the waveguide device, and D of is the duty ratio of the diffraction grating region that the light first passes through in the output diffraction grating pattern after passing through the expanded diffraction grating pattern along the propagation path.

15. The waveguide device according to claim 1, wherein: The duty cycle D of the input diffraction grating pattern in and the duty cycle D of the extended diffraction grating pattern e Satisfies the following formula 8, The ΔD4 of the following formula 9 is 5% or more, [Formula 8] D in >D e , [Formula 9] △D4=100×(D in –D e ) / D e 。 16. The waveguide device according to claim 1, wherein: The pitch P of the input diffraction grating pattern in and the pitch P of the extended diffraction grating pattern e Satisfies the following formula 10, The ΔP2 of the following formula 11 is 5% or more, [Formula 10] P in >P e , [Formula 11] △P2=100×(P in –P e ) / P e 。 17. The waveguide device according to claim 1, wherein: The ΔD5 of the following formula 12 is 5% or more, [Formula 12] △D5=100×(D if –D ef ) / D el In formula 12, D if is the duty cycle of the input diffraction grating pattern, and D ef is the duty ratio of the diffraction grating area that the light first passes through in the extended diffraction grating pattern along the propagation path of the light coupled into the waveguide device.

18. The waveguide device according to claim 1, wherein: Light output area: 35cm 2 or larger.

19. An extended reality device comprising the waveguide device according to any one of claims 1 to 18.

20. A head-up display device, comprising the waveguide device according to any one of claims 1 to 18.

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