TWI804435B - Ocular optical system - Google Patents

Abstract

An ocular optical system configured to allow imaging rays from a display image to enter an observer’s eye through the ocular optical system so as to form an image is provided. A direction toward the eye is an eye side, and a direction toward the display image is a display side. The ocular optical system sequentially includes a first and a second lens elements from the eye side to the display side along an optical axis. Each lens element includes an eye-side surface and a display-side surface. One of an optical axis region of the eye-side surface of the first lens element and an optical axis region of the display-side of the first lens element is plane. An optical axis region of the eye-side surface of the second lens element is plane. Lens elements of the ocular optical system are only the two lens elements. The ocular optical system satisfies following conditional expression: 0.400≦T1/T2≦2.000.

Description

Eyepiece Optical System

The present invention relates to an optical system, and in particular to an eyepiece optical system.

Virtual reality (virtual reality, VR) is the use of computer technology to simulate a three-dimensional virtual world, providing users with visual, auditory and other sensory simulations, allowing users to feel personally on the scene. At present, existing VR devices are mainly based on visual experience. The parallax of human eyes is simulated by splitting images with slightly different viewing angles corresponding to the left and right eyes to achieve stereoscopic vision. In order to reduce the size of the virtual reality device and allow users to obtain a magnified visual experience through a smaller display screen, the eyepiece optical system with magnification function has become one of the subjects of VR research and development.

As far as the existing eyepiece optical system is concerned, the following problems are faced: the viewing angle of the half eye is small, which makes the observer feel that there is a dark scene around the screen, so the user's sense of immersion in the virtual world needs to be improved. In addition, if the half-eye viewing angle is increased, the volume and weight of the lens and the display screen will be doubled. Therefore, how to increase the viewing angle of the half eye and reduce the volume and weight of the system is a problem that needs to be improved for the eyepiece optical system.

The invention provides an eyepiece optical system, which is light and thin, has a larger half-eye viewing angle and good imaging quality.

An embodiment of the present invention provides an eyepiece optical system, which is used to make imaging light enter the observer's eyes from a display screen through the eyepiece optical system for imaging. The direction towards the eye is the eye side. The direction toward the display screen is the display side, and the first lens and the second lens are sequentially included along the optical axis from the eye side to the display side. Each of the first lens and the second lens includes an eye side facing the eye side and allowing the imaging light to pass through, and a display side facing the display side and allowing the imaging light to pass through. One of the optical axis area of the eye side of the first lens and the optical axis area of the display side of the first lens is a plane. The optical axis area of the eye side of the second lens is a plane. The lenses of the eyepiece optical system only have the above two lenses. The eyepiece optical system meets the following conditions: 0.400≦T1/T2≦2.000. T1 is the thickness of the first lens on the optical axis, and T2 is the thickness of the second lens on the optical axis.

An embodiment of the present invention provides an eyepiece optical system, which is used to make imaging light enter the observer's eyes from a display screen through the eyepiece optical system for imaging. The direction towards the eye is the eye side. The direction toward the display screen is the display side, and the first lens and the second lens are sequentially included along the optical axis from the eye side to the display side. Each of the first lens and the second lens includes an eye side facing the eye side and allowing the imaging light to pass through, and a display side facing the display side and allowing the imaging light to pass through. One of the optical axis area of the eye side of the first lens and the optical axis area of the display side of the first lens is a plane. The peripheral area of the eye side of the second lens is a plane. The lenses of the eyepiece optical system only have the above two lenses. The eyepiece optical system meets the following conditions: 0.400≦T1/T2≦2.000. T1 is the thickness of the first lens on the optical axis, and T2 is the thickness of the second lens on the optical axis.

An embodiment of the present invention provides an eyepiece optical system, which is used to make imaging light enter the observer's eyes from a display screen through the eyepiece optical system for imaging. The direction towards the eye is the eye side. The direction toward the display screen is the display side, and the first lens and the second lens are sequentially included along the optical axis from the eye side to the display side. Each of the first lens and the second lens includes an eye side facing the eye side and allowing the imaging light to pass through, and a display side facing the display side and allowing the imaging light to pass through. One of the optical axis area of the eye side of the first lens and the optical axis area of the display side of the first lens is a plane. The lenses of the eyepiece optical system only have the above two lenses. The eyepiece optical system meets the following conditions: TTL≦47.657mm and 0.400≦T1/T2≦2.000. TTL is the distance from the eye side of the first lens to the display screen on the optical axis, T1 is the thickness of the first lens on the optical axis, and T2 is the thickness of the second lens on the optical axis.

An embodiment of the present invention provides an eyepiece optical system, which is used to make imaging light enter the observer's eyes from a display screen through the eyepiece optical system for imaging. The direction towards the eye is the eye side. The direction toward the display screen is the display side, and the first lens and the second lens are sequentially included along the optical axis from the eye side to the display side. Each of the first lens and the second lens includes an eye side facing the eye side and allowing the imaging light to pass through, and a display side facing the display side and allowing the imaging light to pass through. One of the optical axis area of the eye side of the second lens and the optical axis area of the display side of the second lens is a plane. The eyepiece optical system meets the following conditions: 0.400≦T1/T2≦2.000. T1 is the thickness of the first lens on the optical axis, and T2 is the thickness of the second lens on the optical axis.

In order to make the above-mentioned features and advantages of the present invention more comprehensible, the following specific embodiments are described in detail together with the accompanying drawings.

Generally speaking, the light direction of the eyepiece optical system V100 is that an imaging light VI is emitted from the display screen V50, enters the eye V60 through the eyepiece optical system V100, and is focused on the retina of the eye V60 to form a magnified virtual image VV at the virtual image distance VD, as shown in Figure 1 shows. In the following, the criterion for judging the optical specifications of this case is assuming that the direction of light rays is reversely tracked (reversely tracking) as a parallel imaging light from the eye side through the eyepiece optical system to the display screen for focusing and imaging.

The optical system in this specification includes at least one lens, which receives the imaging light from the incident optical system parallel to the optical axis to within an angle of half the visual angle (ω) relative to the optical axis. The imaging light is imaged on the display screen through the optical system. The term "a lens has a positive refractive power (or negative refractive power)" means that the paraxial refractive power of the lens calculated by Gaussian optics theory is positive (or negative). The so-called "eye side (or display side) of the lens" is defined as a specific range where imaging light passes through the lens surface. The imaging light includes at least two types of light: a chief ray (chief ray) Lc and a marginal ray (marginal ray) Lm (as shown in FIG. 2 ). The eye side (or display side) of the lens can be divided into different areas according to different positions, including the optical axis area, the circumference area, or one or more relay areas in some embodiments, and the description of these areas will be described in detail below elaborate.

FIG. 2 is a radial cross-sectional view of the lens 100 . Two reference points on the surface of the lens 100 are defined: the center point and the transition point. The center point of the lens surface is an intersection point of the surface and the optical axis I. As shown in FIG. 2 , the first center point CP1 is located on the eye side 110 of the lens 100 , and the second center point CP2 is located on the display side 120 of the lens 100 . The transition point is a point on the lens surface whose tangent is perpendicular to the optical axis I. The optical boundary OB of the lens surface is defined as a point where the radially outermost marginal ray Lm passing through the lens surface intersects the lens surface. All transition points lie between the optical axis I and the optical boundary OB of the lens surface. In addition, if there are multiple conversion points on a single lens surface, the conversion points are named sequentially from the first conversion point from the radial direction outward. For example, the first transition point TP1 (closest to the optical axis I), the second transition point TP2 (as shown in FIG. 5 ), and the Nth transition point (farthest from the optical axis I).

The range from the central point to the first transition point TP1 is defined as the optical axis area, wherein the optical axis area includes the central point. The area from the Nth conversion point farthest from the optical axis I radially outward to the optical boundary OB is defined as the circumferential area. In some embodiments, a relay area between the optical axis area and the circumference area may be further included, and the number of the relay area depends on the number of conversion points.

When the light parallel to the optical axis I passes through a region, if the light is deflected toward the optical axis I and the intersection point with the optical axis I is on the display side A2 of the lens, then the region is a convex surface. After the light rays parallel to the optical axis I pass through a region, if the intersection of the extension line of the light rays and the optical axis I is on the eye side A1 of the lens, the region is a concave surface.

In addition, referring to FIG. 2 , the lens 100 may further include an assembly portion 130 extending radially outward from the optical boundary OB. The assembly part 130 is generally used for assembling the lens 100 to a corresponding element of the optical system (not shown). The imaging light does not reach the assembly part 130 . The structure and shape of the assembling part 130 are only examples for illustrating the present invention, and are not intended to limit the scope of the present invention. The assembly part 130 of the lens discussed below may be partially or completely omitted in the drawings.

Referring to FIG. 3 , the optical axis zone Z1 is defined between the central point CP and the first transition point TP1 . A circumferential zone Z2 is defined between the first transition point TP1 and the optical boundary OB of the lens surface. As shown in FIG. 3 , the parallel ray 211 intersects the optical axis I on the display side A2 of the lens 200 after passing through the optical axis zone Z1 , that is, the focus of the parallel ray 211 passing through the optical axis zone Z1 is located at point R on the display side A2 of the lens 200 . Since the light intersects the optical axis I at the display side A2 of the lens 200, the optical axis area Z1 is a convex surface. On the contrary, the parallel light rays 212 diverge after passing through the circumferential zone Z2. As shown in FIG. 3 , the extension line EL after the parallel ray 212 passes through the circumferential area Z2 intersects the optical axis I on the eye side A1 of the lens 200, that is, the focal point of the parallel ray 212 passing through the circumferential area Z2 is located at point M on the eye side A1 of the lens 200 . Since the extension line EL of the light intersects the optical axis I on the eye side A1 of the lens 200, the circumferential area Z2 is a concave surface. In the lens 200 shown in FIG. 3 , the first transition point TP1 is the boundary between the optical axis area and the circumference area, that is, the first transition point TP1 is the boundary point from the convex surface to the concave surface.

On the other hand, the judgment of the concave-convex surface shape of the optical axis area can also be judged by the common knowledge in this field, that is, the optical axis area surface of the lens can be judged by the sign of the paraxial curvature radius (abbreviated as R value). shaped bumps. R-values are commonly used in optical design software such as Zemax or CodeV. The R-value is also commonly found in the lens data sheet of optical design software. Taking the eye side as an example, when the R value is positive, it is judged that the optical axis area of the eye side is convex; when the R value is negative, it is judged that the optical axis area of the eye side is concave. Conversely, for the display side, when the R value is positive, it is determined that the optical axis area of the display side is concave; when the R value is negative, it is determined that the optical axis area of the display side is convex. The judgment result of this method is consistent with the above-mentioned result of judging the intersection point of the ray/ray extension line and the optical axis. The judgment method of the intersection point of the ray/ray extension line and the optical axis is that the focal point of a ray parallel to the optical axis is located on the lens Use the eye side or the display side to judge the unevenness of the surface. "A region is convex (or concave)", "a region is convex (or concave)" or "a convex (or concave) region" described in this specification can be used interchangeably.

4 to 6 provide examples of judging the surface shape and area boundary of the lens area in each case, including the aforementioned optical axis area, circumference area, and relay area.

FIG. 4 is a radial cross-sectional view of the lens 300 . Referring to FIG. 4 , there is only one transition point TP1 within the optical boundary OB on the display side 320 of the lens 300 . The optical axis area Z1 and the circumferential area Z2 of the display side 320 of the lens 300 are shown in FIG. 4 . This shows that the R value of the side surface 320 is positive (ie R>0), therefore, the optical axis area Z1 is a concave surface.

Generally speaking, the surface shape of each area bounded by the conversion point will be opposite to that of the adjacent area. Therefore, the conversion point can be used to define the transformation of the surface shape, that is, from the conversion point to the concave surface to the convex surface or from the convex surface to the concave surface. In FIG. 4 , since the optical axis zone Z1 is a concave surface, and the surface shape changes at the transition point TP1 , the peripheral zone Z2 is a convex surface.

FIG. 5 is a radial cross-sectional view of the lens 400 . Referring to FIG. 5 , there is a first transition point TP1 and a second transition point TP2 on the eye side 410 of the lens 400 . The optical axis area Z1 of the eye surface 410 is defined between the optical axis I and the first transition point TP1. The R value of the eye side surface 410 is positive (ie R>0), therefore, the optical axis area Z1 is a convex surface.

A circumferential area Z2 is defined between the second transition point TP2 and the optical boundary OB of the eye side 410 of the lens 400 , and the circumferential area Z2 of the eye side 410 is also a convex surface. In addition, a relay zone Z3 is defined between the first transition point TP1 and the second transition point TP2 , and the relay zone Z3 of the target surface 410 is a concave surface. Referring again to FIG. 5 , the eye side 410 sequentially includes the optical axis area Z1 between the optical axis I and the first transition point TP1 from the radial direction outward of the optical axis I, and is located between the first transition point TP1 and the second transition point TP2 The relay zone Z3 of , and the circumferential zone Z2 between the second transition point TP2 and the optical boundary OB of the eye side 410 of the lens 400 . Since the optical axis area Z1 is convex, the surface shape changes from the first transition point TP1 to concave, so the relay area Z3 is concave, and the surface shape changes from the second transition point TP2 to convex again, so the circumferential area Z2 is convex.

FIG. 6 is a radial cross-sectional view of the lens 500 . The eye side 510 of the lens 500 has no transition point. For a lens surface without a conversion point, such as the eye side 510 of the lens 500, the optical axis area is defined as 0-50% of the distance from the optical axis I to the optical boundary OB of the lens surface, and from the optical axis I to the lens surface optical 50~100% of the distance between the boundaries OB is the circumference area. Referring to the lens 500 shown in FIG. 6, 50% of the distance from the optical axis I to the optical boundary OB on the surface of the lens 500 is defined as the optical axis area Z1 of the eye side 510. The R value of the eye side surface 510 is positive (that is, R>0), therefore, the optical axis area Z1 is a convex surface. Since the eye side 510 of the lens 500 has no transition point, the circumferential area Z2 of the eye side 510 is also convex. The lens 500 may further have an assembly portion (not shown) extending radially outward from the circumferential area Z2.

FIG. 7A is a schematic diagram of lens cutting shape and lens parameters according to an embodiment of the present invention. FIG. 7B is a schematic diagram of the cropped shape of the display screen and the parameters of the display screen according to the embodiment of the present invention. Please refer to FIG. 7A and FIG. 7B. Since the eyepiece optical system of the embodiment of the present invention has a large half-eye viewing angle design, the lens and the display screen cannot cover the maximum viewing angle of a single eye because of the pupil distance PD (Pupil Distance, PD) factor of the two eyes. The corresponding display image circle ICD (image circle diameter, ICD), so the shape of the lens of the embodiment of the present invention needs to be cut and the shape of the display screen is also changed, as shown in Figure 7A and Figure 7B respectively, and the effective The display screen is the part where the display image circle ICD of the two eyes overlaps with the display area AA of the display D (ie, the area indicated by the oblique lines). Lens parameters and display parameters are defined in detail in the following paragraphs.

From a macro perspective, the details of the Fresnel surface shape of the lens of the embodiment of the present invention are relatively small and it is difficult to see the specific shape. In order to describe the Fresnel surface of the embodiment of the present invention in detail, please refer to FIG. 8 , FIG. 8 is an enlarged schematic diagram of a Fresnel surface, for example, a schematic diagram of a convex Fresnel surface. In the embodiment of the present invention, the Fresnel surface F (Fresnel surface) represents the surface of a Fresnel lens (Fresnel lens). The Fresnel surface F has a plurality of concentric annular teeth surrounding a Fresnel surface center FC, which surrounds a central convex surface PC. Each ring tooth has an effective sub-surface P1 capable of refracting incident light to a predetermined direction and an ineffective sub-surface P2 connecting two adjacent effective sub-surfaces P1. These effective sub-surfaces P1 and the central convex surface PC refract the incident light to a predetermined direction.

9 is a schematic diagram of the eyepiece optical system of the first embodiment of the present invention, and FIGS. 10A to 10D are diagrams of longitudinal spherical aberration and various aberrations of the eyepiece optical system of the first embodiment. Please refer to Fig. 9 first, the eyepiece optical system 10 of the first embodiment of the present invention is used to make the imaging light of the display screen 99 enter the observer's eyes through the eyepiece optical system 10 and the pupil O of the observer's eyes to form an image, and the display screen 99 is the vertical optical axis, in order to correct various aberrations of the imaging light, avoiding the aberration of a certain side having an oblique angle with the optical axis when it is not equal to 90 degrees with the optical axis I. The eye side A1 is the side facing the direction of the observer's eyes, and the display side A2 is the side facing the direction of the display screen 99 . In this embodiment, the eyepiece optical system 10 includes a first lens 1 and a second lens 2 in sequence along an optical axis I from the eye side A1 to the display side A2. After the imaging light of the display screen 99 is emitted, it passes through the second lens 2 and the first lens 1 in sequence, and then enters the observer's eyes through the observer's pupil 0 . Then, the imaging light will form an image on the retina of the observer's eye.

Specifically, the first lens 1 to the second lens 2 of the eyepiece optical system 10 each have an eye side 15 and 25 facing the eye side A1 and allowing the imaging light to pass through, and facing the display side A2 and allowing the imaging light to pass. The display side 16 and 26 .

In addition, in order to meet the requirement of lightweight products, both the first lens 1 and the second lens 2 have refractive power and are made of plastic material, but the materials of the first lens 1 and the second lens 2 are not limited thereto. In this embodiment, the lenses with refractive power in the eyepiece optical system 10 are only the first lens 1 and the second lens 2 .

The first lens 1 has positive refractive power. The optical axis area 15p1 of the eye side surface 15 of the first lens 1 is a plane, and its peripheral area 15p3 is a plane. The optical axis region 161 of the display side surface 16 of the first lens 1 is convex, and the peripheral region 163 thereof is convex. The display side 16 of the first lens 1 is a Fresnel surface F.

The second lens 2 has a positive refractive power. The optical axis area 25p1 of the eye surface 25 of the second lens 2 is a plane, and its peripheral area 25p3 is a plane. The optical axis region 261 of the display side surface 26 of the second lens 2 is convex, and the peripheral region 263 thereof is convex. The display side 26 of the second lens 2 is a Fresnel surface F. As shown in FIG.

Other detailed optical data of the first embodiment are shown in FIG. 11 . The overall system focal length (effective focal length, EFL) of the eyepiece optical system 10 of the first embodiment is 29.969 millimeters (millimeter, mm), the half-eye visual angle (half apparent field of view, ω) is 65.000 ^∘ , and the aperture value (f -number, Fno) is 7.492. Specifically, the "aperture value" in this specification is an aperture value calculated by considering the observer's pupil 0 as the entrance pupil based on the principle of reversibility of light. In addition, the image height of the eyepiece optical system 10 of the first embodiment is 29.157 mm, and the system length (system length, SL) of the eyepiece optical system 10 of the first embodiment is 44.890 mm, where SL is the pupil 0 of the observer to the display The distance of the picture 99 on the optical axis I. In addition, the effective radius in FIG. 11 means half of the optical effective diameter (clear aperture).

-----------(1) Y：非球面曲線上的點與光軸的距離； Z：非球面深度(非球面上距離光軸為Y的點，與相切於非球面光軸上頂點之切面，兩者間的垂直距離)； R：透鏡表面之曲率半徑； K：圓錐係數； a _i：第i階非球面係數。 In the first embodiment, the display side surfaces 16, 26 of the first lens 1 and the second lens 2 are aspheric surfaces, and the display surfaces 16, 26 of the first lens 1 and the second lens 2 are Fresnel surfaces F, The effective sub-surface of each tooth of the Fresnel surface F is an aspheric surface, and the aspheric coefficients of the sides shown below are used to represent the effective sub-surfaces of these teeth, and these aspheric surfaces are defined according to the following formulas. Curve equation (1) expresses:

-----------(1) Y: the distance between the point on the aspheric curve and the optical axis; Z: the depth of the aspheric surface (the point on the aspheric surface that is Y from the optical The tangent plane of the vertex on the optical axis of the spherical surface, the vertical distance between the two); R: the radius of curvature of the lens surface; K: the cone coefficient; a _i : the i-th order aspheric coefficient.

The various aspheric coefficients of the display sides 16 and 26 in formula (1) are shown in FIG. 12 . Wherein, the column number 16 in FIG. 12 indicates that it is the aspheric coefficient of the display side 16 of the first lens 1 , and the other columns can be deduced by analogy.

In addition, the relationship between various important parameters and conditional expressions in the eyepiece optical system 10 of the first embodiment is shown in FIG. 41 . EPD (Exit pupil diameter) is the exit pupil diameter of the eyepiece optical system 10, corresponding to the diameter of the pupil O of the observer; ER (Eye relief) is the exit pupil distance, the distance from the observer's pupil 0 to the first lens 1 on the optical axis I; ω is the half apparent field of view, which is the half apparent field of view of the observer, as shown in Figure 1; T1 is the thickness of the first lens 1 on the optical axis I; T2 is the thickness of the second lens 1 on the optical axis I; G12 is the air gap between the first lens 1 and the second lens 2 on the optical axis I; G2D is the distance from the second lens 2 to the display screen 99 on the optical axis I; D1 is the longest distance that the display side 16 of the first lens 1 passes through the center FC of the Fresnel surface F, as shown in FIG. 7A , where the center FC refers to the optical center of the Fresnel surface F, that is, the Fresnel surface the center around which the annular teeth of F surround; D2 is the longest side of the display screen 99, that is, the long side of the display area AA of the display D, as shown in FIG. 7B; D3 is the width of the display side 16 of the first lens 1 passing through the center FC of the Fresnel surface F and parallel to the longest side of the display screen 99, as shown in FIG. 7A ; D4 is the longest distance from the display side 16 of the first lens 1 from the center FC of the Fresnel surface F to the circumference CF of the first lens 1, as shown in FIG. 7A ; ImgH is the image height of eyepiece optical system 10; ALT is the sum of the thicknesses of the first lens 1 and the second lens 2 on the optical axis I, that is, the sum of T1 and T2; TL is the distance on the optical axis I from the eye side 15 of the first lens 1 to the display side 26 of the second lens 2; TTL is the distance from the eye side 15 of the first lens 1 to the display screen 99 on the optical axis I; SL is the system length, the distance from the observer's pupil 0 to the display screen 99 on the optical axis I; EFL is the system focal length of the eyepiece optical system 10 . Also, redefine: f1 is the focal length of the first lens 1; f2 is the focal length of the second lens 2; n1 is the refractive index of the first lens 1; n2 is the refractive index of the second lens 2; V1 is the Abbe number of the first lens 1; V2 is the Abbe number of the second lens 2 .

Refer to Fig. 10A to Fig. 10D. Fig. 10A to Fig. 10D are diagrams of various aberrations of the eyepiece optical system of the first embodiment, and it is assumed that the direction of the ray is traced in reverse, and a parallel imaging ray passes through the pupil sequentially from the eye side A1 0 and the various aberration diagrams obtained by focusing and imaging from the eyepiece optical system 10 to the display screen 99. In this embodiment, the various aberrations shown in the above-mentioned various aberration diagrams will determine the various aberrations of the imaging light from the display screen 99 on the retina of the observer's eyes. That is to say, when the various aberrations shown in the above-mentioned various aberration diagrams are small, the various aberrations of the imaging of the retina of the observer's eyes will also be small, so that the observer can watch good image.

Specifically, the diagram of FIG. 10A illustrates the longitudinal spherical aberration (longitudinal spherical aberration) of the first embodiment, and the diagrams of FIG. 10B and FIG. 10C respectively illustrate the field curvature in the sagittal direction of the first embodiment ( field curvature) aberration and field curvature aberration in the meridian (tangential) direction, and the diagram in FIG. 10D illustrates the distortion aberration of the first embodiment. The longitudinal spherical aberration diagram in FIG. 10A of the first embodiment is simulated when the pupil radius (pupil radius) is 2.000 mm (that is, when the exit pupil diameter EPD of the eyepiece optical system 10 is 4.000 mm). In addition, in the longitudinal spherical aberration diagram of the first embodiment shown in FIG. 10A , the curves formed by each wavelength are very close to the middle, indicating that the off-axis light rays of different heights for each wavelength are concentrated near the imaging point. It can be seen from the skewness of the curve of each wavelength that the imaging point deviation of off-axis rays at different heights is controlled within the range of ±0.49 mm, so this embodiment does significantly improve the spherical aberration of the same wavelength. In addition, the 486 nm The distances between the three representative wavelengths of , 588nm and 656nm are also quite close, which means that the imaging positions of light of different wavelengths are quite concentrated, so that the chromatic aberration is also significantly improved.

In the two diagrams of field curvature aberration in Fig. 10B and Fig. 10C, the field curvature aberrations of the three representative wavelengths in the entire field of view fall within the range of ±3.00 mm, illustrating the eyepiece optical system of the first embodiment 10 can effectively eliminate aberrations. The distortion aberration diagram in FIG. 10D shows that the distortion aberration of the first embodiment is maintained within the range of ±60%, indicating that the distortion aberration of the first embodiment has met the imaging quality requirements of the optical system. According to this It shows that compared with the existing eyepiece optical system, this first embodiment can still provide better imaging quality under the condition that the SL has been shortened to about 44.890 mm, so this first embodiment can maintain good optical performance The eyepiece optical system is shortened to realize a thinner product design. In addition, the eyepiece optical system 10 of the first embodiment has a larger viewing angle of the eye, and can correct aberrations while maintaining good imaging quality.

13 is a schematic diagram of the eyepiece optical system of the second embodiment of the present invention, and FIGS. 14A to 14D are diagrams of longitudinal spherical aberration and various aberrations of the eyepiece optical system of the second embodiment. Please refer to FIG. 13 , a second embodiment of the eyepiece optical system 10 of the present invention, which is roughly similar to the first embodiment, and the differences between the two are as follows. The second embodiment is more or less different from the first embodiment in terms of optical data, aspheric coefficients, and parameters of the first lens 1 to the second lens 2 . It should be noted here that, in order to clearly show the drawing, the labels of the optical axis area and the circumferential area similar to those of the first embodiment are omitted in FIG. 13 .

The detailed optical data of the eyepiece optical system 10 of the second embodiment is shown in Figure 13, and the overall system focal length of the eyepiece optical system 10 of the second embodiment is 19.795 mm, the half-eye viewing angle (ω) is 68.000∘, and the aperture value ( Fno) is 4.949, the image height is 29.828 mm, and the SL is 35.565 mm.

As shown in FIG. 16 , it is the various aspheric coefficients in the formula (1) of the display sides 16 and 26 of the first lens 1 to the second lens 2 of the second embodiment.

In addition, the relationship between various important parameters in the eyepiece optical system 10 of the second embodiment is shown in FIG. 41 .

The longitudinal spherical aberration diagram of the second embodiment shown in FIG. 14A is simulated when the pupil radius is 2.000 mm (that is, when the exit pupil diameter EPD of the eyepiece optical system 10 is 4.000 mm). The longitudinal spherical aberration diagram of the second embodiment is shown in FIG. 14A , and the imaging point deviation of off-axis rays at different heights is controlled within the range of ±0.36 mm. In the illustrations of the two field curvature aberrations in FIG. 14B and FIG. 14C , the field curvature aberrations of the three representative wavelengths in the entire field of view fall within the range of ±13.00 mm. The distortion aberration diagram of FIG. 14D shows that the distortion aberration of the second embodiment is maintained within the range of ±40%. This shows that compared with the existing eyepiece optical system, the second embodiment can still provide better imaging quality under the condition that the SL has been shortened to about 35.565 mm.

It can be seen from the above description that the advantage of the second embodiment over the first embodiment is that the system length of the second embodiment is smaller than that of the first embodiment. The aperture of the second embodiment is larger than that of the first embodiment. The half-eye viewing angle of the second embodiment is larger than that of the first embodiment. The longitudinal spherical aberration of the second embodiment is smaller than that of the first embodiment. The field curvature of the second embodiment is smaller than that of the first embodiment.

17 is a schematic diagram of the eyepiece optical system of the third embodiment of the present invention, and FIGS. 18A to 18D are diagrams of longitudinal spherical aberration and various aberrations of the eyepiece optical system of the third embodiment. Please refer to FIG. 17 , which shows a third embodiment of the eyepiece optical system 10 of the present invention, which is roughly similar to the first embodiment, and the main differences between the two are as follows. The optical data, aspheric coefficients, and parameters of the first lens 1 to the second lens 2 of the third embodiment are more or less different from the first embodiment. It should be noted here that, in order to clearly show the drawing, the labels of the optical axis area and the circumferential area similar to those of the first embodiment are omitted in FIG. 17 .

The detailed optical data of the eyepiece optical system 10 of the third embodiment is shown in Figure 19, and the overall system focal length of the eyepiece optical system 10 of the third embodiment is 29.530 mm, the half-eye viewing angle (ω) is 65.000 ^∘ , and the aperture value ( Fno) is 7.382, the image height is 29.009 mm, and the SL is 46.287 mm.

As shown in FIG. 20 , it is the various aspheric coefficients in formula (1) of the display sides 16 and 26 of the first lens 1 to the second lens 2 of the third embodiment.

In addition, the relationship between various important parameters in the eyepiece optical system 10 of the third embodiment is shown in FIG. 41 .

The longitudinal spherical aberration diagram of the third embodiment shown in FIG. 18A is simulated when the pupil radius is 2.000 mm (that is, when the exit pupil diameter EPD of the eyepiece optical system 10 is 4.000 mm). The longitudinal spherical aberration diagram of the third embodiment is shown in FIG. 18A , and the imaging point deviation of off-axis rays at different heights is controlled within the range of ±0.53 mm. In the two diagrams of field curvature aberration in FIG. 18B and FIG. 18C , the field curvature aberrations of the three representative wavelengths in the entire field of view fall within the range of ±2.80 mm. The distortion aberration diagram of FIG. 18D shows that the distortion aberration of the third embodiment is maintained within the range of ±55%. Accordingly, compared with the existing eyepiece optical system, the third embodiment can still provide better imaging quality under the condition that the SL has been shortened to about 46.287 mm.

It can be known from the above description that the advantage of the third embodiment compared with the first embodiment is that the aperture of the third embodiment is larger than that of the first embodiment. The field curvature of the third embodiment is smaller than that of the first embodiment.

21 is a schematic diagram of the eyepiece optical system of the fourth embodiment of the present invention, and FIGS. 22A to 22D are diagrams of longitudinal spherical aberration and various aberrations of the eyepiece optical system of the fourth embodiment. Please refer to FIG. 21 , which shows a fourth embodiment of the eyepiece optical system 10 of the present invention, which is roughly similar to the first embodiment, and the main differences between the two are as follows. The optical data, aspheric coefficients, and parameters of the first lens 1 to the second lens 2 of the fourth embodiment are more or less different from those of the first embodiment. Furthermore, in the fourth embodiment, the display side 26 of the second lens 2 is not a Fresnel surface, but a general aspheric surface. The optical axis region 26p1 of the display side surface 26 of the second lens 2 is a plane, and its peripheral region 263 is a convex surface. It should be noted here that, in order to clearly show the figure, in FIG. 21 , the labels of the optical axis area and the circumferential area similar to those of the first embodiment are omitted.

The detailed optical data of the eyepiece optical system 10 of the fourth embodiment is shown in Figure 23, and the overall system focal length of the eyepiece optical system 10 of the fourth embodiment is 34.077 mm, the half-eye viewing angle (ω) is 69.000 ^∘ , and the aperture value ( Fno) is 8.519, the image height is 33.665 mm, and the SL is 46.229 mm.

As shown in FIG. 24 , it is the various aspheric coefficients in formula (1) of the display sides 16 and 26 of the first lens 1 to the second lens 2 of the fourth embodiment. It should be noted that although the display side 26 is not a Fresnel surface, formula (1) still applies.

In addition, the relationship among various important parameters in the eyepiece optical system 10 of the fourth embodiment is shown in FIG. 41 .

The diagram of longitudinal spherical aberration in FIG. 22A of the fourth embodiment is simulated when the pupil radius is 2.000 mm (that is, when the exit pupil diameter EPD of the eyepiece optical system 10 is 4.000 mm). The longitudinal spherical aberration diagram of the fourth embodiment is shown in FIG. 22A , and the imaging point deviation of off-axis rays at different heights is controlled within the range of ±0.59 mm. In the illustrations of the two field curvature aberrations in FIG. 22B and FIG. 22C , the field curvature aberrations of the three representative wavelengths in the entire field of view fall within the range of ±4.50 mm. The distortion aberration diagram of FIG. 22D shows that the distortion aberration of the fourth embodiment is maintained within the range of ±60%. This shows that compared with the existing eyepiece optical system, the fourth embodiment can still provide better imaging quality under the condition that the SL has been shortened to about 46.229 mm.

From the above description, it can be seen that the advantage of the fourth embodiment compared with the first embodiment is that the half-eye viewing angle of the fourth embodiment is larger than the half-eye viewing angle of the first embodiment.

25 is a schematic diagram of the eyepiece optical system of the fifth embodiment of the present invention, and FIGS. 26A to 26D are diagrams of longitudinal spherical aberration and various aberrations of the eyepiece optical system of the fifth embodiment. Please refer to FIG. 25 , a fifth embodiment of the eyepiece optical system 10 of the present invention, which is roughly similar to the first embodiment, and the main differences between the two are as follows. The optical data, aspheric coefficients, and parameters of the first lens 1 to the second lens 2 of the fifth embodiment are more or less different from the first embodiment. It should be noted here that, in order to clearly show the figure, the labels of the optical axis area and the circumferential area similar to those of the first embodiment are omitted in FIG. 25 .

The detailed optical data of the eyepiece optical system 10 of the fifth embodiment is shown in Figure 27, and the overall system focal length of the eyepiece optical system 10 of the fifth embodiment is 41.848 mm, the half-eye viewing angle (ω) is 65.000 ^∘ , and the aperture value ( Fno) is 10.462, the image height is 33.636 mm, and the SL is 61.657 mm.

As shown in FIG. 28 , it is the various aspheric coefficients in formula (1) of the display sides 16 and 26 of the first lens 1 to the second lens 2 of the fifth embodiment.

In addition, the relationship among various important parameters in the eyepiece optical system 10 of the fifth embodiment is shown in FIG. 41 .

The longitudinal spherical aberration diagram of the fifth embodiment shown in FIG. 26A is simulated when the pupil radius is 2.000 mm (that is, when the exit pupil diameter EPD of the eyepiece optical system 10 is 4.000 mm). The longitudinal spherical aberration diagram of the fifth embodiment is shown in FIG. 26A , and the imaging point deviation of off-axis rays at different heights is controlled within the range of ±0.53 mm. In the illustrations of the two field curvature aberrations in FIG. 26B and FIG. 26C , the field curvature aberrations of the three representative wavelengths in the entire field of view fall within the range of ±13.00 mm. The distortion aberration diagram of FIG. 26D shows that the distortion aberration of the fifth embodiment is maintained within the range of ±62%. This shows that compared with the existing eyepiece optical system, the fifth embodiment can still provide better imaging quality under the condition that the SL has been shortened to about 61.657 mm.

It can be seen from the above description that the advantage of the fifth embodiment compared with the first embodiment is that the manufacturing difficulty of the fifth embodiment is relatively low so that the yield rate is high.

29 is a schematic diagram of the eyepiece optical system of the sixth embodiment of the present invention, and FIGS. 30A to 30D are diagrams of longitudinal spherical aberration and various aberrations of the eyepiece optical system of the sixth embodiment. Please refer to FIG. 29 , which shows a sixth embodiment of the eyepiece optical system 10 of the present invention, which is roughly similar to the first embodiment, and the main differences between the two are as follows. The optical data, aspheric coefficients, and parameters of the first lens 1 to the second lens 2 of the sixth embodiment are somewhat different from those of the first embodiment. Furthermore, in the sixth embodiment, the eye side 15 of the first lens 1 is convex, its optical axis area 151 is convex, and its circumference area 153 is convex. It should be noted here that, in order to clearly show the drawing, the labels of the optical axis area and the circumferential area similar to those of the first embodiment are omitted in FIG. 29 .

The detailed optical data of the eyepiece optical system 10 of the sixth embodiment is shown in Figure 31, and the overall system focal length of the eyepiece optical system 10 of the sixth embodiment is 24.391 mm, the half-eye viewing angle (ω) is 65.000 ^∘ , and the aperture value ( Fno) is 6.098, the image height is 23.814 mm, and the SL is 37.789 mm.

As shown in FIG. 32 , it is the various aspheric coefficients in the formula (1) of the display sides 16 and 26 of the first lens 1 to the second lens 2 of the sixth embodiment.

In addition, the relationship among various important parameters in the eyepiece optical system 10 of the sixth embodiment is shown in FIG. 41 .

The diagram 30A of the longitudinal spherical aberration diagram of the sixth embodiment is simulated when the pupil radius is 2.000 mm (that is, when the exit pupil diameter EPD of the eyepiece optical system 10 is 4.000 mm). The longitudinal spherical aberration diagram of the sixth embodiment is shown in FIG. 30A , and the imaging point deviation of off-axis rays at different heights is controlled within the range of ±0.48 mm. In the diagrams of the two field curvature aberrations in FIG. 30B and FIG. 30C , the field curvature aberrations of the three representative wavelengths in the entire field of view fall within the range of ±1.60 mm. The distortion aberration diagram in FIG. 30D shows that the distortion aberration of the sixth embodiment is maintained within the range of ±55%. This shows that compared with the existing eyepiece optical system, the sixth embodiment can still provide better imaging quality under the condition that the SL has been shortened to about 37.789 mm.

It can be known from the above description that the advantage of the sixth embodiment compared with the first embodiment is that the aperture of the sixth embodiment is larger than that of the first embodiment. The system length of the sixth embodiment is smaller than that of the first embodiment. The field curvature of the sixth embodiment is smaller than that of the first embodiment.

33 is a schematic diagram of the eyepiece optical system of the seventh embodiment of the present invention, and FIGS. 34A to 34D are diagrams of longitudinal spherical aberration and various aberrations of the eyepiece optical system of the seventh embodiment. Please refer to FIG. 33 , a seventh embodiment of the eyepiece optical system 10 of the present invention, which is roughly similar to the first embodiment, and the main differences between the two are as follows. The seventh embodiment is more or less different from the first embodiment in terms of optical data, aspheric coefficients, and parameters of the first lens 1 to the second lens 2 . Furthermore, in the seventh embodiment, the eye side 15 of the first lens 1 is convex, its optical axis area 151 is convex, and its circumference area 153 is convex. The optical axis region 251 of the eye surface 25 of the second lens 2 is convex, and its peripheral region 253 is convex. It should be noted here that, in order to clearly show the drawing, the labels of the optical axis area and the circumferential area similar to those of the first embodiment are omitted in FIG. 33 .

The detailed optical data of the eyepiece optical system 10 of the seventh embodiment is shown in Figure 35, and the overall system focal length of the eyepiece optical system 10 of the seventh embodiment is 33.108 mm, the half-eye viewing angle (ω) is 67.500 ^∘ , and the aperture value ( Fno) is 8.277, image height is 36.000 mm, and SL is 50.215 mm.

As shown in FIG. 36 , it is the various aspheric coefficients in the formula (1) of the display sides 16 and 26 of the first lens 1 to the second lens 2 of the seventh embodiment.

In addition, the relationship among various important parameters in the eyepiece optical system 10 of the seventh embodiment is shown in FIG. 41 .

The diagram of longitudinal spherical aberration in the seventh embodiment shown in FIG. 34A is simulated when the pupil radius is 2.000 mm (that is, when the exit pupil diameter EPD of the eyepiece optical system 10 is 4.000 mm). The longitudinal spherical aberration diagram of the seventh embodiment is shown in FIG. 34A , and the imaging point deviation of off-axis rays at different heights is controlled within the range of ±0.49 mm. In the diagrams of the two field curvature aberrations in FIG. 34B and FIG. 34C , the field curvature aberrations of the three representative wavelengths in the entire field of view fall within the range of ±23.00 mm. The distortion aberration diagram of FIG. 34D shows that the distortion aberration of the seventh embodiment is maintained within the range of ±55%. This shows that compared with the existing eyepiece optical system, the seventh embodiment can still provide better imaging quality under the condition that the SL has been shortened to about 50.215 mm.

From the above description, it can be known that the advantage of the seventh embodiment compared with the first embodiment is that the half-eye viewing angle of the seventh embodiment is larger than the half-eye viewing angle of the first embodiment.

37 is a schematic diagram of the eyepiece optical system of the eighth embodiment of the present invention, and FIGS. 38A to 38D are diagrams of longitudinal spherical aberration and various aberrations of the eyepiece optical system of the eighth embodiment. Please refer to FIG. 37 , an eighth embodiment of the eyepiece optical system 10 of the present invention, which is roughly similar to the first embodiment, and the main differences between the two are as follows. The optical data, aspheric coefficients, and parameters of the first lens 1 to the second lens 2 of the eighth embodiment are somewhat different from those of the first embodiment. Furthermore, in the eighth embodiment, the eye surface 15 of the first lens 1 is concave, the optical axis region 152 thereof is concave, and the circumference region 154 thereof is concave. The optical axis region 252 of the eye surface 25 of the second lens 2 is concave, and its peripheral region 254 is concave. It should be noted here that, in order to clearly show the drawing, the labels of the optical axis area and the circumferential area similar to those of the first embodiment are omitted in FIG. 37 .

The detailed optical data of the eyepiece optical system 10 of the eighth embodiment is shown in Figure 39, and the overall system focal length of the eyepiece optical system 10 of the eighth embodiment is 32.784 mm, the half-eye viewing angle (ω) is 67.500 ^∘ , and the aperture value ( Fno) is 37.517, image height is 35.995 mm, and SL is 50.517 mm.

As shown in FIG. 40 , it is the various aspheric coefficients in the formula (1) of the display sides 16 and 26 of the first lens 1 to the second lens 2 of the eighth embodiment.

In addition, the relationship among various important parameters in the eyepiece optical system 10 of the eighth embodiment is shown in FIG. 41 .

The diagram of longitudinal spherical aberration in the eighth embodiment shown in FIG. 38A is simulated when the pupil radius is 2.000 mm (that is, when the exit pupil diameter EPD of the eyepiece optical system 10 is 4.000 mm). The longitudinal spherical aberration diagram of the eighth embodiment is shown in FIG. 38A , and the imaging point deviation of off-axis rays at different heights is controlled within the range of ±0.49 mm. In the diagrams of the two field curvature aberrations in FIG. 38B and FIG. 38C , the field curvature aberrations of the three representative wavelengths in the entire field of view fall within the range of ±23.00 mm. The distortion aberration diagram of FIG. 38D shows that the distortion aberration of the eighth embodiment is maintained within the range of ±55%. This shows that compared with the existing eyepiece optical system, the eighth embodiment can still provide better imaging quality under the condition that the SL has been shortened to about 50.517 mm.

It can be seen from the above description that the advantage of the eighth embodiment compared with the first embodiment is that the half-eye viewing angle of the eighth embodiment is larger than that of the first embodiment.

Refer to Figure 41 again. FIG. 41 is a tabular view of various optical parameters of the above-mentioned first to eighth embodiments. Among the parameters in the columns from "EFL" to "TL", except that the unit of "ω" is degree (°), and the units of "V1" and "V2" are dimensionless, the units of the parameters in other columns are millimeter (mm). Among the parameters in the columns "ω/TL" to "EFL/TL", except for the unit of "ω/TL" which is °/mm, the units of the parameters in other columns are dimensionless.

For the following conditional expressions, the purpose of at least one of them is to maintain an appropriate value of the system focal length and optical parameters, avoiding any parameter that is too large to be unfavorable for the correction of the aberration of the eyepiece optical system 10 as a whole, or avoiding any parameter Too small will affect the assembly or increase the difficulty of manufacturing. in, The eyepiece optical system 10 can meet the conditional formula: 6.000≦EFL/T1, and the preferred range is 6.000≦EFL/T1≦24.000. The eyepiece optical system 10 can meet the conditional formula: 6.000≦EFL/T2, preferably in the range of 6.000≦EFL/T2≦24.000. The eyepiece optical system 10 can meet the conditional formula: 4.490≦EFL/ALT, and the preferred range is 4.490≦EFL/ALT≦12.000. The eyepiece optical system 10 can meet the conditional formula: 4.300≦ EFL/TL, and the preferred range is 4.300≦EFL/TL≦12.000.

For the following conditional expressions, the purpose of at least one of them is to make the thickness and spacing of each lens maintain an appropriate value, to avoid any parameter being too large and not conducive to the thinning of the eyepiece optical system 10 as a whole, or to avoid any parameter being too small and affecting Assembling or increasing the difficulty of manufacturing. in, The eyepiece optical system 10 can meet the conditional formula: 0.400≦T1/T2, and the preferred range is 0.400≦T1/T2≦2.000. The eyepiece optical system 10 can meet the conditional formula: 1.500≦T1/G12, and the preferred range is 1.500≦T1/G12≦19.000. The eyepiece optical system 10 can meet the conditional formula: 1.800≦T2/G12, and the preferred range is 1.800≦T2/G12≦19.000. The eyepiece optical system 10 can meet the conditional formula: 4.630≦TTL/ALT, and the preferred range is 4.630≦TTL/ALT≦13.500. The eyepiece optical system 10 can meet the conditional formula: 4.340≦TTL/TL, and the preferred range is 4.340≦TTL/TL≦12.000. The eyepiece optical system 10 can meet the conditional formula: 5.500≦G2D/T1, and the preferred range is 5.500≦G2D/T1≦22.000. The eyepiece optical system 10 can meet the conditional formula: 5.500≦G2D/T2, and the preferred range is 5.500≦G2D/T2≦22.000.

In addition, arbitrary combinations of parameters in the embodiment can be selected to increase system constraints, so as to facilitate the system design of the same architecture of the present invention. In view of the unpredictability of optical system design, under the framework of the present invention, meeting the above conditions can better shorten the length of the present invention, increase the aperture, improve the imaging quality, or improve the assembly yield and improve the prior art. shortcoming.

In addition, with regard to the exemplary limiting relational expressions listed above, different numbers can also be arbitrarily and selectively combined and applied in the implementation of the present invention, and are not limited thereto. When implementing the present invention, in addition to the aforementioned relational expressions, other detailed structures such as the concave-convex surface arrangement of the lens can also be designed for the lens, so as to strengthen the control of the system performance and/or resolution. It should be noted that these details should be selectively combined and applied to other embodiments of the present invention under the condition of no conflict.

The numerical ranges including the maximum and minimum values obtained from the combined proportional relationship of the optical parameters disclosed in the various embodiments of the present invention can be implemented accordingly.

In summary, the eyepiece optical system 10 of the embodiment of the present invention can obtain the following effects and advantages:

1. The longitudinal spherical aberration, astigmatic aberration, and distortion of each embodiment of the present invention conform to the usage specification. In addition, red, green, and blue off-axis rays representing wavelengths at different heights are all concentrated near the imaging point, and the deviation of the imaging point of off-axis rays at different heights can be seen from the skewness of each curve. Good ability to suppress spherical aberration, aberration and distortion. Further referring to the imaging quality data, the distances between the three representative wavelengths of red, green and blue are also quite close, showing that the present invention has good concentration to different wavelengths of light under various conditions and has excellent dispersion suppression ability, and can produce excellent Image quality.

2. The eyepiece optical system 10 of the embodiment of the present invention is combined by the following lens design: (1) The optical axis region 161 of the display side 16 of the first lens 1 is a convex surface and the display side 16 is a Fresnel surface F. (2) The optical axis region 261 or the peripheral region 263 of the display side surface 26 of the second lens 2 is a convex surface. In addition, with the conditional formula 6.500°/mm≦ω/TL≦30.000°/mm, 0.970≦D1/D2≦1.500 or 0.850≦D3/D2≦1.400, the focus imaging of the eyepiece optical system 10 will be shared between the two pieces with a positive tendency The refractive power of the lens is beneficial to increase the half-eye viewing angle of the system without increasing the volume and weight of the system while maintaining the size of the display screen 99 .

3. When the display side 26 of the second lens 2 is a Fresnel surface F, it can solve the problem that the peripheral area becomes thinner and difficult to assemble under the premise of increasing the refractive index of the peripheral area of the lens to achieve half the viewing angle of the eye, and can The volume and weight of the second lens 2 are reduced.

4. When the eye side 15 of the first lens 1 is convex, the imaging quality in the middle of the display screen 99 is better, and the refractive index of the Fresnel surface F on the display side 16 can be reduced to improve the yield. When the eye side 15 of the first lens 1 is a concave surface, because the concave surface conforms to the convex surface of the human eye, the comfort of the observer can be improved. In addition, the imaging quality around the display screen 99 is better, and the half-eye viewing angle is easier to improve. When the eye side 15 of the first lens 1 is flat, it is easier to balance the imaging quality between the center and the periphery of the display screen 99 , and it is easier to manufacture and improve the yield rate.

5. When the conditional formula 4.000≦D4/ALT or the conditional formula 3.750≦D4/TL is satisfied and combined with the above shapes, it is beneficial to increase the optical effective diameter of the lens without increasing the thickness of the lens. The above conditional expressions are preferably limited to 4.000≦D4/ALT≦19.500 and 3.750≦D4/TL≦17.400, respectively.

6. When the conditional expression 1.100≦ω/arctan(D4/EFL) is satisfied and combined with the above shape, it is beneficial to increase the semi-eye viewing angle of the system and reduce the size of the display screen 99 at the same time. The conditional expression is preferably limited to 1.100≦ ω/arctan (D4/EFL)≦2.250. Among them, arctan represents the arc tangent function.

Although the present invention has been disclosed above with the embodiments, it is not intended to limit the present invention. Anyone with ordinary knowledge in the technical field may make some changes and modifications without departing from the spirit and scope of the present invention. The scope of protection of the present invention should be defined by the scope of the appended patent application.

0: pupil 1: First lens 10. V100: eyepiece optical system 100, 200, 300, 400, 500: lens 130: Assembly Department 15, 25, 110, 410, 510: Mesh side 16, 26, 120, 320: display side 2: Second lens 211, 212: Parallel rays AA: display area F: Fresnel surface FC: Center of the Fresnel surface 99. V50: display screen A1: eye side A2: Display side CP: center point CF: Circumference CP1: first center point CP2: second center point D: monitor D1, D3, D4: lens parameters D2: display screen parameters EL: extension line EPD: exit pupil diameter I: optical axis ImgH: image height ICD: display like circle Lm: edge light Lc: chief light OB: Optical Boundary M, R: intersection point PC: Central Convex PD: pupillary distance P1: effective sub-surface P2: invalid sub-surface TP1: first transition point TP2: Second transition point V60: eyes VD: virtual image distance VI: imaging light VV: Magnified virtual image Z1, 15p1, 151, 152, 161, 25p1, 251, 252, 261, 26p1: optical axis area Z2, 15p3, 153, 154, 163, 25p3, 253, 254, 263: Circumferential area ω: half-eye viewing angle Z3: relay zone

Fig. 1 is a schematic diagram illustrating an eyepiece optical system. Fig. 2 is a schematic diagram illustrating the surface structure of a lens. FIG. 3 is a schematic diagram illustrating the surface concave-convex structure of a lens and the focal point of light. FIG. 4 is a schematic diagram illustrating the surface structure of a lens of Example 1. FIG. FIG. 5 is a schematic diagram illustrating the surface structure of a second example lens. FIG. 6 is a schematic diagram illustrating a surface structure of a third example lens. FIG. 7A is a schematic diagram illustrating the lens cut shape and lens parameters of the embodiment of the present invention. FIG. 7B is a schematic diagram illustrating the cropped shape of the display screen and the parameters of the display screen according to the embodiment of the present invention. FIG. 8 is a schematic diagram illustrating a Fresnel surface of an embodiment of the present invention. Fig. 9 is a schematic diagram of the eyepiece optical system of the first embodiment of the present invention. 10A to 10D are diagrams of longitudinal spherical aberration and various aberrations of the eyepiece optical system of the first embodiment. FIG. 11 shows detailed optical data of the eyepiece optical system of the first embodiment of the present invention. FIG. 12 shows the aspheric parameters of the eyepiece optical system of the first embodiment of the present invention. FIG. 13 is a schematic diagram of the eyepiece optical system of the second embodiment of the present invention. 14A to 14D are graphs of longitudinal spherical aberration and various aberrations of the eyepiece optical system of the second embodiment. FIG. 15 shows detailed optical data of the eyepiece optical system of the second embodiment of the present invention. FIG. 16 shows the aspheric parameters of the eyepiece optical system of the second embodiment of the present invention. FIG. 17 is a schematic diagram of an eyepiece optical system according to a third embodiment of the present invention. 18A to 18D are diagrams of longitudinal spherical aberration and various aberrations of the eyepiece optical system of the third embodiment. FIG. 19 shows detailed optical data of the eyepiece optical system of the third embodiment of the present invention. FIG. 20 shows the aspheric parameters of the eyepiece optical system of the third embodiment of the present invention. FIG. 21 is a schematic diagram of an eyepiece optical system according to a fourth embodiment of the present invention. 22A to 22D are graphs of longitudinal spherical aberration and various aberrations of the eyepiece optical system of the fourth embodiment. Fig. 23 shows the detailed optical data of the eyepiece optical system of the fourth embodiment of the present invention. FIG. 24 shows the aspheric parameters of the eyepiece optical system of the fourth embodiment of the present invention. Fig. 25 is a schematic diagram of an eyepiece optical system according to a fifth embodiment of the present invention. 26A to 26D are graphs of longitudinal spherical aberration and various aberrations of the eyepiece optical system of the fifth embodiment. Fig. 27 shows the detailed optical data of the eyepiece optical system of the fifth embodiment of the present invention. Fig. 28 shows the aspheric parameters of the eyepiece optical system of the fifth embodiment of the present invention. Fig. 29 is a schematic diagram of the eyepiece optical system of the sixth embodiment of the present invention. 30A to 30D are diagrams of longitudinal spherical aberration and various aberrations of the eyepiece optical system of the sixth embodiment. Fig. 31 shows the detailed optical data of the eyepiece optical system of the sixth embodiment of the present invention. Fig. 32 shows the aspheric parameters of the eyepiece optical system of the sixth embodiment of the present invention. Fig. 33 is a schematic diagram of the eyepiece optical system of the seventh embodiment of the present invention. 34A to 34D are diagrams of longitudinal spherical aberration and various aberrations of the eyepiece optical system of the seventh embodiment. Fig. 35 shows the detailed optical data of the eyepiece optical system of the seventh embodiment of the present invention. Fig. 36 shows the aspheric parameters of the eyepiece optical system of the seventh embodiment of the present invention. Fig. 37 is a schematic diagram of the eyepiece optical system of the eighth embodiment of the present invention. 38A to 38D are diagrams of longitudinal spherical aberration and various aberrations of the eyepiece optical system of the eighth embodiment. Fig. 39 shows the detailed optical data of the eyepiece optical system of the eighth embodiment of the present invention. FIG. 40 shows the aspheric parameters of the eyepiece optical system of the eighth embodiment of the present invention. Fig. 41 shows the values of various important parameters and their relational expressions of the eyepiece optical system of the first to eighth embodiments of the present invention.

0: pupil 1: First lens 10: Eyepiece optical system 15, 25: eye side 16, 26: display side 2: Second lens F: Fresnel surface 99: display screen A1: eye side A2: Display side I: optical axis 15p1, 161, 25p1, 261: optical axis area 15p3, 163, 25p3, 263: Circumferential area ω: half-eye viewing angle

Claims (20)

An eyepiece optical system, which is used to make imaging light enter the observer's eyes from a display screen through the eyepiece optical system for imaging. The direction toward the eye is an eye side, and the direction toward the display screen is a display side. The display side includes a first lens and a second lens in sequence along an optical axis, and each of the first lens and the second lens includes an eye side facing the eye side and allowing the imaging light to pass through and an eye side facing the display side and the side of the display through which the imaging light passes; one of an optical axis area and a circumferential area of the eye side of the second lens is flat; The lens of the eyepiece optical system has only the above two lenses; and The eyepiece optical system meets the following conditional formula: 4.340≦TTL/TL, where TTL is the distance from the eye side of the first lens to the display screen on the optical axis, and TL is the distance from the eye side of the first lens to the The distance of the display side surface of the second lens on the optical axis. An eyepiece optical system, which is used to make imaging light enter the observer's eyes from a display screen through the eyepiece optical system for imaging. The direction toward the eye is an eye side, and the direction toward the display screen is a display side. The display side includes a first lens and a second lens in sequence along an optical axis, and each of the first lens and the second lens includes an eye side facing the eye side and allowing the imaging light to pass through and an eye side facing the display side and the side of the display through which the imaging light passes; one of an optical axis region and a circumferential region of the eye side of the first lens is concave; one of an optical axis region and a circumferential region of the eye side of the second lens is concave; The lens of the eyepiece optical system has only the above two lenses; and The eyepiece optical system meets the following conditional formula: 4.340≦TTL/TL, where TTL is the distance from the eye side of the first lens to the display screen on the optical axis, and TL is the distance from the eye side of the first lens to the The distance of the display side surface of the second lens on the optical axis. The eyepiece optical system as described in claim 1 or claim 2, wherein the eyepiece optical system more meets the following conditional formula: 1.500≦T1/G12≦19.000, wherein T1 is a thickness of the first lens on the optical axis , and G12 is an air gap between the first lens and the second lens on the optical axis. The eyepiece optical system according to claim 1 or claim 2, wherein the eyepiece optical system more meets the following conditional formula: 6.500°/mm≦ω/TL≦30.000°/mm, where ω is the half-eye viewing angle. The eyepiece optical system as described in claim 1 or claim 2, wherein the eyepiece optical system more meets the following conditional formula: 6.000≦EFL/T1, where EFL is the system focal length of the eyepiece optical system, and T1 is the first A thickness of the lens on the optical axis. The eyepiece optical system as described in claim 1 or claim 2, wherein the eyepiece optical system more meets the following conditional formula: 4.630≦TTL/ALT, where ALT is the first lens and the second lens on the optical axis the sum of the thicknesses. The eyepiece optical system as claimed in claim 1 or claim 2, wherein the display side of the first lens is a Fresnel surface, and the eyepiece optical system more meets the following conditional formula: 3.750≦D4/TL, where D4 is a longest distance of the display side of the first lens from the center of the Fresnel surface to the circumference of the first lens. The eyepiece optical system as described in claim 1 or claim 2, wherein the eyepiece optical system more meets the following conditional formula: 0.400≦T1/T2≦2.000, where T1 is a thickness of the first lens on the optical axis , and T2 is a thickness of the second lens on the optical axis. The eyepiece optical system as described in Claim 1 or Claim 2, wherein the eyepiece optical system further meets the following conditional formula: 4.300≦EFL/TL, where EFL is the system focal length of the eyepiece optical system. The eyepiece optical system as described in claim 1 or claim 2, wherein the eyepiece optical system more meets the following conditional formula: 5.500≦G2D/T2, where G2D is the distance from the second lens to the display screen on the optical axis distance, and T2 is a thickness of the second lens on the optical axis. The eyepiece optical system as described in claim 1 or claim 2, wherein the eyepiece optical system more meets the following conditional formula: 5.500≦G2D/T1, where G2D is the distance from the second lens to the display screen on the optical axis distance, and T1 is a thickness of the first lens on the optical axis. An eyepiece optical system, which is used to make imaging light enter the observer's eyes from a display screen through the eyepiece optical system for imaging. The direction toward the eye is an eye side, and the direction toward the display screen is a display side. The display side includes a first lens and a second lens in sequence along an optical axis, and each of the first lens and the second lens includes an eye side facing the eye side and allowing the imaging light to pass through and an eye side facing the display side and the side of the display through which the imaging light passes; one of an optical axis region and a circumferential region of the eye side of the first lens is concave; one of an optical axis region and a circumferential region of the eye side of the second lens is concave; The lens of the eyepiece optical system has only the above two lenses; and The eyepiece optical system meets the following conditional formula: 5.500≦G2D/T1, wherein G2D is the distance from the second lens to the display screen on the optical axis, and T1 is a thickness of the first lens on the optical axis. The eyepiece optical system according to claim 1, claim 2 or claim 12, wherein the display side of the first lens is a Fresnel surface. The eyepiece optical system as described in claim 1, claim 2 or claim 12, wherein the display side of the first lens is a Fresnel surface, and the eyepiece optical system more meets the following conditional formula: 4.000≦D4 /ALT, where D4 is the longest distance from the center of the Fresnel surface to the circumference of the first lens on the display side of the first lens, and ALT is the distance between the first lens and the second lens on the optical axis The sum of the thicknesses above. The eyepiece optical system as described in claim 1, claim 2 or claim 12, wherein the eyepiece optical system more meets the following conditional formula: 1.800≦T2/G12≦19.000, where T2 is the second lens on the optical axis and G12 is an air gap between the first lens and the second lens on the optical axis. The eyepiece optical system as described in claim 1, claim 2 or claim 12, wherein the display side of the first lens is a Fresnel surface, and the eyepiece optical system more meets the following conditional formula: 0.970≦D1 /D2≦1.500, wherein D1 is a longest distance between the display side of the first lens passing through the center of the Fresnel surface, and D2 is the longest side of the display screen. The eyepiece optical system as described in claim 1, claim 2 or claim 12, wherein the eyepiece optical system is more in line with the following conditional formula: 6.000≦EFL/T2, where EFL is the system focal length of the eyepiece optical system, and T2 is a thickness of the second lens on the optical axis. The eyepiece optical system as described in claim 1, claim 2 or claim 12, wherein the display side of the first lens is a Fresnel surface, and the eyepiece optical system more meets the following conditional formula: 0.850≦D3 /D2≦1.400, wherein D2 is the longest side of the display screen, and D3 is the width of the display side of the first lens passing through the center of the Fresnel surface and parallel to the longest side of the display screen. The eyepiece optical system as described in claim 1, claim 2 or claim 12, wherein the display side of the first lens is a Fresnel surface, and the eyepiece optical system more meets the following conditional formula: 1.100≦ω /arctan(D4/EFL), where ω is the semi-eye viewing angle, D4 is the longest distance from the center of the Fresnel surface to the circumference of the first lens on the display side of the first lens, and EFL is the eyepiece optics The system focal length of the system. The eyepiece optical system as described in claim 1, claim 2 or claim 12, wherein the eyepiece optical system is more in line with the following conditional formula: 4.490≦EFL/ALT, where EFL is the system focal length of the eyepiece optical system, and ALT is the sum of the thicknesses of the first lens and the second lens on the optical axis.

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