TW202012992A - 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 having refractive power 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. An optical axis region of a display-side surface of the first lens element is convex. The display-side surface of the first lens element is a Fresnel surface. An optical axis region or a periphery region of a display-side surface of the second lens element is convex.

Description

Eyepiece optical system

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

Virtual reality (VR) is the use of computer technology to generate a virtual world in a three-dimensional space, providing users with sensory simulations of vision, hearing, etc., so that users can feel personally in the world. At present, the existing VR devices are mainly based on visual experience. The stereoscopic vision is achieved by simulating the parallax of the human eye by splitting the pictures corresponding to the two different angles of view of the left and right eyes. In order to reduce the size of the virtual reality device and allow users to get a magnified visual experience through the smaller display screen, the eyepiece optical system with magnification function has become one of the topics of VR research and development.

As far as the existing eyepiece optical system is concerned, the following problems are encountered: the half-eye viewing angle is small, which makes the viewer feel that there is a dark screen around the picture, so the user's 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 half-eye viewing angle 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 has a light and thin, larger half-eye viewing angle and good imaging quality.

An embodiment of the present invention provides an eyepiece optical system for imaging light rays from a display screen through an eyepiece optical system to enter an observer's eye for imaging. The direction toward the eyes 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. The first lens and the second lens each include a mesh side facing the eye side and passing the imaging light, and a display side facing the display side and passing the imaging light. The optical axis area of the display side of the first lens is convex and the display side of the first lens is a Fresnel surface. The optical axis area or the circumferential area of the display side surface of the second lens is convex. The lens of the eyepiece optical system with refractive power is only the above two lenses. The eyepiece optical system meets the following conditions: 6.500°/mm≦ω/TL≦30.000°/mm. ω is the half-eye viewing angle of the eyepiece optical system, and TL is the distance on the optical axis from the eye side of the first lens to the display side of the second lens.

An embodiment of the present invention provides an eyepiece optical system for imaging light rays from a display screen through an eyepiece optical system to enter an observer's eye for imaging. The direction toward the eyes 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. The first lens and the second lens each include a mesh side facing the eye side and passing the imaging light, and a display side facing the display side and passing the imaging light. The optical axis area of the display side of the first lens is convex and the display side of the first lens is a Fresnel surface. The optical axis area or the circumferential area of the display side surface of the second lens is convex. The lens of the eyepiece optical system with refractive power is only the above two lenses. The eyepiece optical system meets the following conditions: 0.970≦D1/D2≦1.500. D1 is the longest distance between the eye side of the first lens and the center of the Fresnel surface, and D2 is the longest side of the display screen.

An embodiment of the present invention provides an eyepiece optical system for imaging light rays from a display screen through an eyepiece optical system to enter an observer's eye for imaging. The direction toward the eyes 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. The first lens and the second lens each include a mesh side facing the eye side and passing the imaging light, and a display side facing the display side and passing the imaging light. The optical axis area of the display side of the first lens is convex and the display side of the first lens is a Fresnel surface. The optical axis area or the circumferential area of the display side surface of the second lens is convex. The lens of the eyepiece optical system with refractive power is only the above two lenses. The eyepiece optical system meets the following conditions: 0.850≦D3/D2≦1.400. D2 is the longest side of the display screen, and D3 is the distance that the eye side of the first lens passes through the center of the Fresnel surface and is parallel to the longest side of the display screen.

Based on the above, in the eyepiece optical system of the embodiment of the present invention, the surface design of the first lens and the second lens is combined with any of the following three conditional expressions: (1).6.500°/mm ≦ω/TL≦30.000°/mm, (2).0.970≦D1/D2≦1.500 or (3).0.850≦D3/D2≦1.400, which can increase the half-eye view of the system without increasing the volume and weight of the system Viewing angle while maintaining the size of the display screen, and has good imaging quality.

In order to make the above-mentioned features and advantages of the present invention more obvious and understandable, the embodiments are specifically described below in conjunction with the accompanying drawings for detailed description as follows.

Generally speaking, the light direction of the eyepiece optical system V100 is an imaging light VI exiting the display screen V50, enters the eye V60 through the eyepiece optical system V100, focuses on the retina of the eye V60, and produces an enlarged virtual image VV at the virtual image distance VD, such as Figure 1. The judgment criterion for explaining the optical specifications of the case below is to assume that the direction of the light rays is reversely tracking (reversely tracking) as a parallel imaging ray from the eye side through the eyepiece optical system to the focused image of the display screen.

The optical system in this specification includes at least one lens that receives imaging light from the incident optical system parallel to the optical axis to a half-eye viewing 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 positive refractive power (or negative refractive power)" means that the paraxial refractive power of the lens calculated by Gaussian optical theory is positive (or negative). The "eye side (or display side) of the lens" is defined as the specific range of imaging light passing through the lens surface. The imaging rays include at least two types of rays: chief ray Lc and 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 circumferential area, or one or more relay areas in some embodiments, the description of these areas will be detailed 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 conversion point. The center point of the lens surface is an intersection point of the surface and the optical axis I. As illustrated 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 conversion point is a point on the lens surface, and the tangent to this point is perpendicular to the optical axis I. The optical boundary OB of the lens surface is defined as a point where the edge light ray Lm passing through the lens surface in the radial direction intersects the lens surface. All conversion points are located between the optical axis I and the optical boundary OB of the lens surface. In addition, if there are a plurality of conversion points on the surface of a single lens, the conversion points are named sequentially from the first conversion point in the radial outward direction. For example, the first conversion point TP1 (closest to the optical axis I), the second conversion point TP2 (as shown in FIG. 5), and the Nth conversion point (farthest from the optical axis I).

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

After the light of the parallel optical axis I passes through an area, if the light is deflected toward the optical axis I and the intersection with the optical axis I is on the lens display side A2, the area is convex. After the rays of the parallel optical axis I pass through an area, if the intersection of the extension line of the light and the optical axis I is on the lens side A1, the area is concave.

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 (not shown) of an optical system. The imaging light does not reach the assembly part 130. The structure and shape of the assembling part 130 are only examples for explaining the present invention, and do not limit the scope of the present invention. The lens assembly 130 discussed below may be partially or completely omitted in the drawings.

Referring to FIG. 3, an optical axis region Z1 is defined between the center point CP and the first conversion point TP1. A circular zone Z2 is defined between the first conversion 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 region Z1, that is, the focal point of the parallel ray 211 passing through the optical axis region Z1 is located at the point R of the display side A2 of the lens 200. Since the light rays intersect the optical axis I on the display side A2 of the lens 200, the optical axis region Z1 is a convex surface. Conversely, the parallel 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 through the circumferential area Z2 is located at the point M on the eye side A1 of the lens 200 . Since the extension line EL of the light rays intersects the optical axis I on the eye side A1 of the lens 200, the circumferential region Z2 is concave. In the lens 200 shown in FIG. 3, the first conversion point TP1 is the boundary between the optical axis region and the circumferential region, that is, the first conversion point TP1 is the boundary between the convex surface and the concave surface.

On the other hand, the judgment of the surface shape unevenness of the optical axis area can also be determined according to the judgment method of the ordinary knowledge in the field, that is, the optical axis area surface of the lens is judged by the sign of the paraxial curvature radius (abbreviated as R value) Shaped bumps. The R value can be commonly used in optical design software, such as Zemax or CodeV. The R value is also commonly found in lens data sheets of optical design software. For the eye surface, when the R value is positive, the optical axis area of the eye surface is determined to be convex; when the R value is negative, the optical axis area of the eye surface is determined to be concave. Conversely, regarding the display side, when the R value is positive, the optical axis region of the display side is determined to be concave; when the R value is negative, the optical axis region of the display side is determined to be convex. The result of this method is consistent with the result of the above method of determining the intersection point of the light/ray extension line and the optical axis. The method of determining the intersection point of the light/ray extension line and the optical axis is that the focus of the light with a parallel optical axis is located on the lens The surface side or the display side is used to judge the surface unevenness. The "one area is convex (or concave)", "one area is convex (or concave)" or "one convex (or concave) area" described in this manual can be used instead.

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

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

In general, the area 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 change of the surface shape, that is, from the conversion point from a concave surface to a convex surface or from a convex surface to a concave surface. In FIG. 4, since the optical axis region Z1 is a concave surface and the surface shape changes at the switching point TP1, the circumferential region 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 conversion point TP1 and a second conversion point TP2 on the eye side 410 of the lens 400. The optical axis region Z1 of the mesh side 410 is defined between the optical axis I and the first conversion point TP1. The R value of this mesh side surface 410 is positive (that is, R>0), therefore, the optical axis region Z1 is a convex surface.

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

6 is a radial cross-sectional view of the lens 500. FIG. The eye side 510 of the lens 500 has no switching point. For a lens surface without a conversion point, for example, the eye side 510 of the lens 500, define 0-50% of the distance from the optical axis I to the optical boundary OB of the lens surface as the optical axis region, and from the optical axis I to the lens surface optics 50 to 100% of the distance between the boundaries OB is the circumferential area. Referring to the lens 500 shown in FIG. 6, 50% of the distance from the optical axis I to the optical boundary OB of the surface of the lens 500 from the optical axis I is defined as the optical axis region Z1 of the eye side 510. The R value of the side surface 510 is positive (that is, R>0), therefore, the optical axis region Z1 is convex. Since the eye side 510 of the lens 500 has no switching 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 zone Z2.

7A is a schematic diagram of a lens cutting shape and lens parameters according to an embodiment of the invention. 7B is a schematic diagram of a display screen cutting shape and display screen parameters according to an embodiment of the invention. Please refer to FIG. 7A and FIG. 7B. Since the eyepiece optical system of the embodiment of the present invention has a half-eye viewing angle design, the lens and the display screen cannot cover the maximum single-eye viewing angle due to the factor of PD (Pupil Distance, PD) between 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 cropped and the shape of the display screen also changes, as shown in FIG. 7A and FIG. 7B, respectively, and effective The display screen is a portion where the display image circle ICD of the two eyes overlaps the display area AA of the display D (that is, the slanted area mark). 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. For a detailed description of the Fresnel surface of the embodiment of the present invention, please refer to FIG. 8 FIG. 8 is an enlarged schematic diagram of the 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 the Fresnel lens. The Fresnel surface F has a plurality of concentric ring teeth surrounded by the center FC of the Fresnel surface, which surrounds a central convex surface PC. Each ring-shaped 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 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 longitudinal spherical aberration and various aberration diagrams 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 eye through the eyepiece optical system 10 and the pupil 0 of the observer’s eye for imaging, and display the screen 99 is the vertical optical axis, which facilitates the correction of various aberrations of the imaging light, and avoids the aberration of one side having an oblique angle with the optical axis caused by an angle 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 the present 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. When the imaging light of the display screen 99 is emitted, it will pass through the second lens 2 and the first lens 1 in sequence, and then enter the eyes of the observer through the pupil 0 of the observer. 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 display side surfaces 15 and 25 that face the eye side A1 and pass imaging light rays toward the display side A2 and display side surfaces 16 and 26 that pass imaging light rays .

In addition, in order to meet the demand for lightweight products, both the first lens 1 and the second lens 2 have refractive power and are made of plastic materials, but the materials of the first lens 1 and the second lens 2 are not limited thereto. In the present 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 a positive refractive power. The optical axis region 15p1 of the eye side surface 15 of the first lens 1 is flat, and the circumferential region 15p3 thereof is flat. The optical axis region 161 of the display side surface 16 of the first lens 1 is convex, and its circumferential region 163 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 region 25p1 of the eye side surface 25 of the second lens 2 is flat, and the circumferential region 25p3 thereof is flat. The optical axis region 261 of the display side surface 26 of the second lens 2 is convex, and its circumferential region 263 is convex. The display side 26 of the second lens 2 is a Fresnel surface F.

The other detailed optical data of the first embodiment is shown in FIG. 11. The eyepiece optical system 10 of the first embodiment has an effective focal length (EFL) of 29.969 (millimeter, mm), a half apparent field of view (ω) of 65.000 ^∘ , and an aperture value (f -number, Fno) is 7.492. Specifically, the "aperture value" in this specification is an aperture value calculated by considering the pupil 0 of the observer as the entrance pupil based on the principle of light reversibility. In addition, the image height of the eyepiece optical system 10 of the first embodiment is 29.157 mm, and the system length (SL) of the eyepiece optical system 10 of the first embodiment is 44.890 mm, where SL is the pupil of the observer 0 to the display The distance of the picture 99 on the optical axis I. In addition, the effective radius in FIG. 11 refers to 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 sides 16, 26 of the first lens 1 and the second lens 2 are both aspherical, and the display sides 16, 26 of the first lens 1 and the second lens 2 are the Fresnel surface F, Where the effective sub-surface of each tooth of this Fresnel surface F is an aspheric surface, and the following shows that the aspheric surface coefficient of the side is used to represent the effective sub-surface of these teeth, and these aspheric surfaces are defined according to the following formula The 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 away from the optical axis, and the tangent plane tangent to the vertex on the aspheric optical axis, both Vertical distance); R: radius of curvature of the lens surface; K: conic coefficient; a _i : i-th aspheric coefficient.

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

In addition, the relationship between each important parameter and the conditional expression in the eyepiece optical system 10 of the first embodiment is shown in FIG. 41. EPD (Exit pupil diameter) is the diameter of the exit pupil of the eyepiece optical system 10, which corresponds to the diameter of the pupil 0 of the observer; ER (Eye relief) is the exit pupil distance, the distance from the pupil 0 of the observer to the first lens 1 on the optical axis I; ω is the half apparent field of view, the observer's half angle of view, 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 of the first lens 1 to 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 of the display side 16 of the first lens 1 passing 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 surrounded by the ring teeth of F; 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 of 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 the eyepiece optical system 10; ALT is the total thickness 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 between the eye side 15 of the first lens 1 and the display side 26 of the second lens 2 on the optical axis I; 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 length of the system, the distance from the pupil 0 of the observer to the display screen 99 on the optical axis I; EFL is the system focal length of the eyepiece optical system 10. In addition, 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.

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

Specifically, the diagram of FIG. 10A illustrates the longitudinal spherical aberration of the first embodiment, and the diagrams of FIGS. 10B and 10C illustrate the field curvature of the sagittal direction of the first embodiment ( field curvature) and the field curvature aberration in the tangential direction. The diagram of FIG. 10D illustrates the distortion aberration of the first embodiment. The longitudinal spherical aberration diagram 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 vertical spherical aberration diagram of the first embodiment in FIG. 10A, the curve formed by each wavelength is very close and close to the middle, indicating that the off-axis rays of different heights of each wavelength are concentrated near the imaging point. The deflection amplitude of the curve of each wavelength can be seen, the deviation of the imaging point of off-axis light of different heights is controlled within ±0.49 mm, so this embodiment does significantly improve the spherical aberration of the same wavelength. In addition, 486 nm The distances between the three representative wavelengths of 588 nm and 656 nm are also quite close to each other, and the imaging positions representing light of different wavelengths have been quite concentrated, so that the chromatic aberration is also significantly improved.

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

13 is a schematic diagram of an eyepiece optical system of a second embodiment of the present invention, and FIGS. 14A to 14D are longitudinal spherical aberration and various aberration diagrams of the eyepiece optical system of the second embodiment. Referring first to FIG. 13, a second embodiment of the eyepiece optical system 10 of the present invention is substantially similar to the first embodiment, and the differences between the two are as follows. The second embodiment is more or less different in the optical data, aspheric coefficients, and parameters of the first lens 1 to the second lens 2 in the first embodiment. It should be noted here that in order to clearly show the drawing, the reference numerals of the optical axis area and the circumferential area similar to 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 FIG. 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 aspherical coefficients in the formula (1) of the display side surfaces 16 and 26 of the first lens 1 to the second lens 2 of the second embodiment.

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

The longitudinal spherical aberration diagram 14A of the second 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). In the longitudinal spherical aberration diagram of the second embodiment in FIG. 14A, the deviation of the imaging point of off-axis rays of different heights is controlled within a range of ±0.36 mm. In the two field curvature aberration diagrams of FIGS. 14B and 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%. According to this, 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 known from the above description that the second embodiment has an advantage over the first embodiment in 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 the half-eye viewing angle 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 an eyepiece optical system of a third embodiment of the present invention, and FIGS. 18A to 18D are longitudinal spherical aberration and various aberration diagrams of the eyepiece optical system of the third embodiment. Referring first to FIG. 17, a third embodiment of the eyepiece optical system 10 of the present invention is substantially 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 those of the first embodiment. It should be noted here that in order to clearly show the drawing, the reference numerals of the optical axis area and the circumferential area similar to 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 FIG. 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 aspherical coefficients in the formula (1) of the display side surfaces 16 and 26 of the first lens 1 to the second lens 2 of the third embodiment.

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

The longitudinal spherical aberration diagram 18A of the third 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). In the longitudinal spherical aberration diagram of this third embodiment, as shown in FIG. 18A, the deviation of imaging points of off-axis rays of different heights is controlled within a range of ±0.53 mm. In the two field curvature aberration diagrams of FIGS. 18B and 18C, the field curvature aberrations of the three representative wavelengths within 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 a range of ±55%. According to this, 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 third embodiment has an advantage over the first embodiment in 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 an eyepiece optical system of a fourth embodiment of the present invention, and FIGS. 22A to 22D are longitudinal spherical aberration and various aberration diagrams of the eyepiece optical system of the fourth embodiment. Referring first to FIG. 21, a fourth embodiment of the eyepiece optical system 10 of the present invention is substantially 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 surface 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 flat, and the circumferential region 263 is convex. It should be noted here that, in order to clearly show the drawing, the reference numerals of the optical axis area and the circumferential area similar to those of the first embodiment are omitted in FIG. 21.

Eyepiece optical system 10 of the fourth embodiment detailed optical data 23, the focal length of the overall system and the eyepiece optical system 10 of the fourth embodiment is 34.077 mm, depending on the half angle of view eye ([omega]) of 69.000 ^∘, 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 aspherical coefficients in the formula (1) of the display side surfaces 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 surface 26 is not a Fresnel surface, formula (1) can still be applied.

In addition, the relationship between each important parameter in the eyepiece optical system 10 of the fourth embodiment is shown in FIG. 41.

The longitudinal spherical aberration diagram 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). In the longitudinal spherical aberration diagram of this fourth embodiment, in FIG. 22A, the deviation of the imaging point of off-axis rays of different heights is controlled within a range of ±0.59 mm. In the two field curvature aberration diagrams of FIGS. 22B and 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%. According to this, 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.

It can be known from the above description that the fourth embodiment has an advantage over the first embodiment in that the half-eye viewing angle of the fourth embodiment is larger than the half-eye viewing angle of the first embodiment.

FIG. 25 is a schematic diagram of an eyepiece optical system of a fifth embodiment of the present invention, and FIGS. 26A to 26D are longitudinal spherical aberration and various aberration diagrams of the eyepiece optical system of the fifth embodiment. Referring first to FIG. 25, a fifth embodiment of the eyepiece optical system 10 of the present invention is substantially 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 somewhat different from those of the first embodiment. It should be noted here that in order to clearly show the drawing, the reference numerals of the optical axis area and the circumferential area similar to 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 FIG. 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 aspherical coefficients in the formula (1) of the display side surfaces 16 and 26 of the first lens 1 to the second lens 2 of the fifth embodiment.

In addition, the relationship between each important parameter in the eyepiece optical system 10 of the fifth embodiment is shown in FIG. 41.

The longitudinal spherical aberration diagram 26A of the fifth 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). In the longitudinal spherical aberration diagram of this fifth embodiment, in FIG. 26A, the deviation of the imaging point of off-axis rays of different heights is controlled within a range of ±0.53 mm. In the two field curvature aberration diagrams of FIGS. 26B and 26C, the field curvature aberrations of the three representative wavelengths within 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%. According to this, 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 known from the above description that the fifth embodiment has an advantage over the first embodiment in that the fifth embodiment is less difficult to manufacture and the yield is higher.

FIG. 29 is a schematic diagram of an eyepiece optical system of a sixth embodiment of the present invention, and FIGS. 30A to 30D are longitudinal spherical aberration and various aberration diagrams of the eyepiece optical system of the sixth embodiment. Referring first to FIG. 29, a sixth embodiment of the eyepiece optical system 10 of the present invention is substantially 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 more or less different from those of the first embodiment. In addition, in the sixth embodiment, the eye side surface 15 of the first lens 1 is a convex surface, its optical axis region 151 is a convex surface, and its circumferential region 153 is a convex surface. It should be noted here that in order to clearly show the drawing, the reference numerals of the optical axis area and the circumferential area similar to 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 FIG. 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 aspherical coefficients of the display side surfaces 16 and 26 of the first lens 1 to the second lens 2 in the sixth embodiment in formula (1).

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

The longitudinal spherical aberration diagram 30A 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). In the longitudinal spherical aberration diagram of this sixth embodiment, in FIG. 30A, the deviation of the imaging point of off-axis rays of different heights is controlled within a range of ±0.48 mm. In the two field curvature aberration diagrams of FIGS. 30B and 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 of FIG. 30D shows that the distortion aberration of the sixth embodiment is maintained within a range of ±55%. According to this, 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 sixth embodiment has an advantage over the first embodiment in 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 an eyepiece optical system of a seventh embodiment of the present invention, and FIGS. 34A to 34D are longitudinal spherical aberration and various aberration diagrams of the eyepiece optical system of the seventh embodiment. Referring first to FIG. 33, a seventh embodiment of the eyepiece optical system 10 of the present invention is substantially 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 seventh embodiment are more or less different from those of the first embodiment. In addition, in the seventh embodiment, the eye side surface 15 of the first lens 1 is a convex surface, its optical axis region 151 is a convex surface, and its circumferential region 153 is a convex surface. The optical axis region 251 of the eye side surface 25 of the second lens 2 is convex, and its circumferential region 253 is convex. It should be noted here that in order to clearly show the drawing, the reference numerals of the optical axis area and the circumferential area similar to the first embodiment are omitted in FIG. 33.

10 Detail of the optical data eyepiece optical system according to the seventh embodiment shown in FIG. 35, the seventh embodiment and the embodiment of the eyepiece optical system focal length of the entire system 10 is 33.108 mm, depending on the half angle of view eye ([omega]) of 67.500 ^∘, aperture value ( Fno) is 8.277, the image height is 36.000 mm, and the SL is 50.215 mm.

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

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

The longitudinal spherical aberration diagram 34A of the seventh 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). In the longitudinal spherical aberration diagram of this seventh embodiment, in FIG. 34A, the deviation of the imaging point of off-axis rays of different heights is controlled within a range of ±0.49 mm. In the two field curvature aberration diagrams of FIGS. 34B and 34C, the field curvature aberrations of the three representative wavelengths within 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 a range of ±55%. According to this, 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.

It can be known from the above description that the seventh embodiment has an advantage over the first embodiment in 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 an eyepiece optical system of an eighth embodiment of the present invention, and FIGS. 38A to 38D are longitudinal spherical aberration and various aberration diagrams of the eyepiece optical system of the eighth embodiment. Referring first to FIG. 37, an eighth embodiment of the eyepiece optical system 10 of the present invention is substantially 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 more or less different from those of the first embodiment. In addition, in the eighth embodiment, the eye side surface 15 of the first lens 1 is concave, its optical axis region 152 is concave, and its circumferential region 154 is concave. The optical axis region 252 of the eye side surface 25 of the second lens 2 is concave, and its circumferential region 254 is concave. It should be noted here that in order to clearly show the drawing, the reference numerals of the optical axis area and the circumferential area similar to the first embodiment are omitted in FIG. 37.

10 Detail of the focal length of the entire system optical data eyepiece optical system of the eighth embodiment shown in FIG. 39, and the eyepiece optical system of the eighth embodiment of the embodiment 10 is 32.784 mm, depending on the half angle of view eye ([omega]) of 67.500 ^∘, aperture value ( Fno) is 37.517, the image height is 35.995 mm, and the SL is 50.517 mm.

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

In addition, the relationship between each important parameter in the eyepiece optical system 10 of the eighth embodiment is shown in FIG. 41.

The longitudinal spherical aberration diagram 38A of the eighth 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). In the longitudinal spherical aberration diagram of the eighth embodiment in FIG. 38A, the deviation of the imaging point of off-axis rays of different heights is controlled within a range of ±0.49 mm. In the two field curvature aberration diagrams of FIGS. 38B and 38C, the field curvature aberrations of the three representative wavelengths within 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 a range of ±55%. According to this, 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 known from the above description that the eighth embodiment has an advantage over the first embodiment in that the half-eye viewing angle of the eighth embodiment is larger than that of the first embodiment.

Refer again to Figure 41. FIG. 41 is a table diagram of various optical parameters of the first to eighth embodiments. Among the parameters in the columns from "EFL" to "TL", except the unit of "ω" is degree (°), and the units of "V1" and "V2" are dimensionless, the units of the parameters of the other columns are Millimeter (mm). In the parameters of the columns "ω/TL" to "EFL/TL", the unit of the parameters of the other columns is dimensionless except that the unit of "ω/TL" is °/mm.

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

For the following conditional expressions, at least one of the purposes is to maintain the thickness and interval of each lens at an appropriate value, to avoid that any one of the parameters is too large and is not conducive to the thinning of the eyepiece optical system 10 as a whole, or to avoid the influence of any one of the parameters is too small Assemble or increase the difficulty of manufacturing. among them, The eyepiece optical system 10 can meet the conditional expression: 0.400≦T1/T2, and the preferred range is 0.400≦T1/T2≦2.000. The eyepiece optical system 10 can meet the conditional expression: 1.500≦T1/G12, and the preferred range is 1.500≦T1/G12≦19.000. The eyepiece optical system 10 can meet the conditional expression: 1.800≦T2/G12, and the preferred range is 1.800≦T2/G12≦19.000. The eyepiece optical system 10 can meet the conditional expression: 4.630≦TTL/ALT, and the preferred range is 4.630≦TTL/ALT≦13.500. The eyepiece optical system 10 can meet the conditional expression: 4.340≦TTL/TL, and the preferred range is 4.340≦TTL/TL≦12.000. The eyepiece optical system 10 can meet the conditional expression: 5.500≦G2D/T1, and the preferred range is 5.500≦G2D/T1≦22.000. The eyepiece optical system 10 can meet the conditional expression: 5.500≦G2D/T2, and the preferred range is 5.500≦G2D/T2≦22.000.

In addition, any combination of the parameters of the embodiments can be selected to increase the system limit, which is beneficial to the system design of the same architecture of the present invention. In view of the unpredictability of the design of the optical system, under the framework of the present invention, meeting the above conditional formula can better shorten the length of the present invention, increase the aperture, improve the imaging quality, or improve the assembly yield to improve the prior art. Disadvantages.

In addition, with regard to the above-mentioned exemplary limited relational expressions, arbitrarily and selectively unequal numbers can be combined and applied to the implementation of the present invention, which is not limited thereto. In the implementation of the present invention, in addition to the aforementioned relational expressions, additional details such as the concave-convex curved surface arrangement of the lens can be additionally designed for the lens to enhance the control of system performance and/or resolution. It should be noted that these details need to be selectively applied to other embodiments of the present invention without conflict.

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

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

1. The longitudinal spherical aberration, astigmatic aberration, and distortion of the embodiments of the present invention all comply with the usage specifications. In addition, the three off-axis rays of red, green, and blue wavelengths at different heights are concentrated near the imaging point. From the deflection amplitude of each curve, it can be seen that the deviation of the imaging point of off-axis rays of different heights is controlled and has Good ability to suppress spherical aberration, aberration and distortion. Further referring to the imaging quality data, the three representative wavelengths of red, green, and blue are also very close to each other, showing that the present invention has good concentration of light of different wavelengths in various states and has excellent dispersion suppression ability, which can produce excellent Image quality.

2. The eyepiece optical system 10 of the embodiment of the present invention is combined by the following lens designs: (1) The optical axis region 161 of the display side 16 of the first lens 1 is convex and the display side 16 is the Fresnel surface F. (2) The optical axis region 261 or the circumferential region 263 of the display side surface 26 of the second lens 2 is convex. In addition, with the conditional expression 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 have a positive tendency to be shared between the two lenses. On the lens with the refractive index, it is helpful to increase the half-eye viewing angle of the system and maintain the size of the display screen 99 without increasing the volume and weight of the system.

3. When the display side 26 of the second lens 2 is the Fresnel surface F, it can solve the problem that the circumferential area becomes thin and difficult to assemble under the premise of increasing the refractive index of the lens circumferential area to achieve the majority of the visual angle of view. Reduce the volume and weight of the second lens 2.

4. When the eye side 15 of the first lens 1 is convex, the imaging quality in the middle of the display frame 99 is better, and the refractive index of the Fresnel surface F of the display side 16 can be reduced to improve the yield. When the eye surface 15 of the first lens 1 is concave, the concave surface conforms to the convex structure of the human eye, which can improve the comfort of the observer. 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 surface 15 of the first lens 1 is flat, it is easier to balance the imaging quality of the center and the periphery of the display screen 99. In addition, it is easier to manufacture and it is easy to improve the yield.

5. When the conditional expression 4.000≦D4/ALT or the conditional expression 3.750≦D4/TL is combined with the above combination, 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 met and combined with the above shape combination, it is beneficial to increase the half-eye viewing angle of the system and simultaneously reduce the size of the display screen 99. 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 as above with examples, it is not intended to limit the present invention. Any person with ordinary knowledge in the technical field can make some changes and modifications without departing from the spirit and scope of the present invention. The scope of protection of the present invention shall be subject to the scope defined in the appended patent application.

0: pupil 1: the 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 light AA: display area F: Fresnel surface FC: Center of Fresnel surface 99, V50: display screen A1: Head side A2: Display side CP: center point CF: circumference CP1: the first center point CP2: the second center point D: display D1, D3, D4: lens parameters D2: Display screen parameters EL: extension line EPD: exit pupil diameter I: optical axis ImgH: like height ICD: display like a circle Lm: edge light Lc: chief ray OB: Optical boundary M, R: intersection point PC: Central convex PD: Interpupillary distance P1: Effective subface P2: Invalid sub-face TP1: the first conversion point TP2: second conversion point V60: eyes VD: virtual image distance VI: imaging light VV: magnify the 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 area

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

0: pupil

1: the first lens

10: Eyepiece optical system

15, 25: mesh side

16, 26: Display side

2: second lens

F: Fresnel surface

99: display screen

A1: Head 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 for imaging light from a display screen through the eyepiece optical system to enter the observer's eye for imaging, the direction toward the eye is the eye side, and the direction toward the display screen is the display side, from the eye side to the display The side includes a first lens and a second lens in sequence along an optical axis. The first lens and the second lens each include an eye side facing the eye side and passing imaging light rays, and a face side facing the display side and making The display side through which the imaging light passes; The optical axis area of the display side of the first lens is convex and the display side of the first lens is a Fresnel surface; The optical axis area or the circumferential area of the display side surface of the second lens is convex; The lens of the eyepiece optical system with refractive power is only the above two lenses; and The eyepiece optical system meets the following conditions: 0.970≦D1/D2≦1.500, Wherein, D1 is a longest distance between the eye side of the first lens and the center of the Fresnel surface, and D2 is a longest side of the display screen. An eyepiece optical system for imaging light from a display screen through the eyepiece optical system to enter the observer's eye for imaging, the direction toward the eye is the eye side, and the direction toward the display screen is the display side, from the eye side to the display The side includes a first lens and a second lens in sequence along an optical axis. The first lens and the second lens each include an eye side facing the eye side and passing imaging light rays, and a face side facing the display side and making The display side through which the imaging light passes; The optical axis area of the display side of the first lens is convex and the display side of the first lens is a Fresnel surface; The optical axis area or the circumferential area of the display side surface of the second lens is convex; The lens with optical power of the eyepiece optical system has only the above two lenses; The eyepiece optical system meets the following conditions: 0.850≦D3/D2≦1.400, Wherein, D2 is a longest side of the display screen, and D3 is a distance that the eye side of the first lens passes through the center of the Fresnel surface and is parallel to the longest side direction of the display screen. The eyepiece optical system as described in item 1 or 2 of the patent application range, wherein the eye side of the first lens is convex. The eyepiece optical system as described in item 1 or 2 of the patent application scope, wherein the eyepiece optical system more conforms to the following conditional formula: 4.000≦D4/ALT, where D4 is the display side of the first lens from the Fresnel The longest distance from the center of the ear surface to the circumference of the first lens, and ALT is the sum of the thicknesses of the first lens and the second lens on the optical axis. The eyepiece optical system as described in item 1 or 2 of the patent application scope, wherein the eyepiece optical system more conforms to the following conditional formula: 1.500≦T1/G12≦19.000, 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 as described in item 1 or 2 of the patent application scope, wherein the eyepiece optical system more conforms to the following conditional formula: 4.630≦TTL/ALT, where TTL is the eye side of the first lens to the display screen A distance on the optical axis, and ALT is a sum of thicknesses of the first lens and the second lens on the optical axis. The eyepiece optical system as described in item 1 or 2 of the patent application scope, wherein the eyepiece optical system more conforms to the following conditional formula: 6.000≦EFL/T1, EFL is a system focal length of the eyepiece optical system, and T1 is the first A thickness of a lens on the optical axis. The eyepiece optical system as described in item 1 or 2 of the patent application scope, wherein the eyepiece optical system more conforms to the following conditional formula: 5.500≦G2D/T1, where G2D is from the second lens to the display screen on the optical axis A distance, and T1 is a thickness of the first lens on the optical axis. The eyepiece optical system as described in item 1 or 2 of the patent application range, wherein the eye side of the first lens is concave. The eyepiece optical system as described in item 1 or 2 of the patent application scope, wherein the eyepiece optical system more conforms to the following conditional formula: 3.750≦D4/TL, where D4 is the display side of the first lens from the Fresnel surface Is the longest distance from the center of the first lens to the circumference of the first lens, and TL is a distance on the optical axis from the eye side of the first lens to the display side of the second lens. The eyepiece optical system as described in item 1 or 2 of the patent application scope, wherein the eyepiece optical system more conforms to the following conditional expression: 1.800≦T2/G12≦19.000, T2 is a thickness of 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 item 1 or 2 of the patent application scope, wherein the eyepiece optical system more conforms to the following conditional formula: 4.340≦TTL/TL, TTL is the side of the eye of the first lens to the display screen in the A distance on the optical axis, and TL is a distance on the optical axis from the eye side of the first lens to the display side of the second lens. The eyepiece optical system as described in item 1 or 2 of the patent application scope, wherein the eyepiece optical system more conforms to the following conditional formula: 6.000≦EFL/T2, EFL is a system focal length of the eyepiece optical system, and T2 is the first A thickness of the two lenses on the optical axis. The eyepiece optical system as described in item 1 or 2 of the patent application scope, wherein the eyepiece optical system more conforms to the following conditional formula: 5.500≦G2D/T2, where G2D is the second lens to the display screen on the optical axis A distance, and T2 is a thickness of the second lens on the optical axis. The eyepiece optical system as described in item 1 or 2 of the patent application scope, wherein the display side of the second lens is a Fresnel surface. The eyepiece optical system as described in item 1 or 2 of the patent application scope, wherein the eyepiece optical system more conforms to the following conditional formula: 1.100≦ω/arctan(D4/EFL), ω is the half-eye viewing angle of the eyepiece optical system, D4 is the longest distance of the display side of the first lens from the center of the Fresnel surface to the circumference of the first lens, EFL is a system focal length of the eyepiece optical system, and arctan represents the arc tangent function. The eyepiece optical system as described in item 1 or 2 of the patent application scope, wherein the eyepiece optical system more conforms to the following conditional formula: 0.400≦T1/T2≦2.000, 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 item 1 or 2 of the patent application scope, wherein the eyepiece optical system more conforms to the following conditional formula: 4.300≦EFL/TL, EFL is a system focal length of the eyepiece optical system, and TL is the first A distance on the optical axis from the eye side of a lens to the display side of the second lens. The eyepiece optical system as described in item 1 or 2 of the patent application scope, wherein the eyepiece optical system more conforms to the following conditional expression: 4.490≦EFL/ALT, EFL is a system focal length of the eyepiece optical system, and ALT is the first The total thickness of a lens and the second lens on the optical axis. The eyepiece optical system as described in item 1 or 2 of the patent application scope, wherein the eyepiece optical system more conforms to the following conditional formula: 3.350≦G2D/(T1+G12+T2)≦7.569, G2D is the second lens to the A distance of the display screen on the optical axis, G12 is an air gap between the first lens and the second lens on the optical axis, and T2 is a thickness of the second lens on the optical axis.

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