Wide field image display device

Abstract

A wide field of view image display device is provided with an ocular optical system (OC), a circularly polarizing plate, and a display element (D) arranged in this order from the user's eye side, the OC includes a first lens (L1) and a second lens (L2) arranged in this order from the user's eye side, the surface of the L1 on the user's eye side is aspherical, the surface of the L1 on the D side is a plane or an approximately planar surface on which a reflection polarizing plate and a 1 / 4 wave plate are laminated in this order from the user's eye side, the surface of the L2 on the user's eye side is aspherical, and the portion near the optical axis of the OC in the surface is a convex shape protruding toward the user's eye side or an approximately planar surface, the surface of the L2 on the D side is an aspherical surface of a convex shape protruding toward the D side, and the surface is coated with a half mirror, if the refractive power of the OC and the L1 is set as P0 and P1, and the refractive power of the L2 for image light emitted from the D and traveling along a standard light path is set as P2, then: 0.8 x P0 ≦ P2 ≦ 1.2 x P0, and |P1| < 1 / 4 x P2.

Description

TECHNICAL FIELD

[0001] The present application relates to a wide field of view image display device of a peep type having a folded light path. BACKGROUND

[0002] In recent years, as an example of a wide field of view image display device of a peep type, an HMD (Head Mounted Display) for VR (Virtual Reality) use (hereinafter, referred to as "VR HMD") has begun to attract attention.

[0003] The FOV (Field Of View) (also referred to as "viewing angle") of the VR HMD is wider than that of a general HMD not particularly intended for VR use. For example, the FOV of the general HMD is generally 45° or less, but the FOV of the VR HMD is mostly 90° or more. With respect to the FOV, if 90° is compared with 45°, the value of the FOV is 2 times, but in the diameter of the virtual screen, it is 2.4 times, and in the area thereof, it is 5.8 times. Therefore, in the VR HMD, a higher sense of presence can be given to the user. In addition, it is shown in Non-Patent Literature 1 that the sense of presence increases with an increase in the maximum field angle (viewing angle) of the image, and saturates from around 80° or more.

[0004] As an optical system that can be applied to such a VR HMD, for example, the optical systems described in Patent Literatures 1 and 2 are known.

[0005] PRIOR ART DOCUMENTS

[0006] PATENT LITERATURE

[0007] Patent Literature 1: Japanese Patent Application Laid-Open No. 2020-519964

[0008] Patent Literature 2: Japanese Patent Application Laid-Open No. 2020-510238

[0009] NON-PATENT LITERATURE

[0010] Non-Patent Literature 1: Toyohiko HATA, Haruo SAKATA, Hideo HISSA, "Directional Sensation Induction Effect by Picture Size", The Transactions of the Institute of Television Engineers of Japan, Vol. 33, (1979), No. 5, P. 407-413 SUMMARY

[0011] PROBLEMS TO BE SOLVED BY THE INVENTION

[0012] In a wide field of view image display device of the peep type such as a VR use HMD, it is desirable to allow a user to visually recognize an image of a wide field of view (FOV of 80° or more) and high resolution, and it is desirable to be small (thin), light, excellent in mass productivity, and low in manufacturing cost.

[0013] However, the reality is that a scheme satisfying all of these requirements has not yet been realized. For example, in a case where the optical system described in Patent Literature 1 is applied to realize a wide field of view image display device of the peep type, there are problems as follows.

[0014] In the optical system described in Patent Literature 1, a reflective polarizing plate is disposed on a curved main surface of an optical lens. In this way, in order to dispose the reflective polarizing plate on a curved surface, a special manufacturing method is required, and there are problems in cost increase and further in reliability.

[0015] It is difficult to dispose a retardation layer on a curved surface in terms of a manufacturing method, and in the optical system described in Patent Literature 1, the retardation layer is disposed on a flat or substantially flat main surface of the optical lens on the side of an imager of a radiation image (so-called display panel). Therefore, the optical lens on the side of the display panel cannot correct optical aberration by configuring the main surface on which the retardation layer is disposed as an aspherical surface with a large sag. This lens, which loses the unit to effectively correct aberration, cannot enhance the refractive power. This is because, if the refractive power is enhanced, the aberration increases and cannot be offset. As a result, the magnification of the optical system described in Patent Literature 1 is limited. Also, in order to obtain a large FOV (80° or more), it is necessary to increase the size of the display panel, and thus the following two problems remain.

[0016] 1. If the size of the display panel is increased, the entire device becomes large and heavy.

[0017] 2. If the size of the display panel is increased, a light beam (harmful light beam) that exits from the display surface and directly passes without traveling along a standard light path (i.e., not reflected even once) becomes thick, particularly in the optical lens adjacent to the display surface. Also, in order to block this light and obtain a clear image, it is necessary to reduce its birefringence in the entire region through which the light beam passes in the optical lens. Since birefringence easily occurs in the peripheral portion of a plastic lens, a plastic lens cannot be used for this optical lens, and a glass lens has to be used. However, the manufacturing cost of a glass lens is high compared to a plastic lens, and this is particularly true for an aspherical lens. Also, a glass lens is heavier than a plastic lens. In addition, even a glass lens, for example, if it is manufactured by molding, birefringence becomes large in the peripheral portion of the lens, and much effort is required in terms of the manufacturing method.

[0018] Such problems also occur in a case where the optical system described in Patent Literature 2 is applied to realize a wide field of view image display device of the peep type.

[0019] The present application has been made in view of the above-described circumstances, and has an object to provide a peep-type wide field of view image display device that is small (thin) and light, has excellent mass productivity, and has low manufacturing cost, and that enables a user to visually recognize a wide field of view (FOV of 80° or more) and a high-resolution image.

[0020] Means for solving the problem

[0021] One embodiment of the present application is a wide field of view image display device that is a peep-type wide field of view image display device, characterized by including, in order from the eye side of a user, an eyepiece optical system, a circularly polarizing plate, and a display element, the eyepiece optical system including, in order from the eye side of the user, a first lens and a second lens, a first surface of the first lens, which is a surface on the eye side of the user, being an aspherical surface, a second surface of the first lens, which is a surface on the display element side, being a flat surface or an approximately flat surface, a reflection polarizing plate and a 1 / 4 wave plate being stacked in order from the eye side of the user on the second surface, a third surface of the second lens, which is a surface on the eye side of the user, being an aspherical surface, and a portion of the third surface near an optical axis of the eyepiece optical system being a convex shape that protrudes toward the eye side of the user or an approximately flat surface, a fourth surface of the second lens, which is a surface on the display element side, being an aspherical surface of a convex shape that protrudes toward the display element side, and a half mirror being coated on the fourth surface, if a refractive power of the eyepiece optical system is P0, a refractive power of the first lens is P1, and a refractive power of the second lens with respect to image light that exits from the display element and travels along a standard light path is P2, then 0.8 x P0 ≦ P2 ≦ 1.2 x P0, and |P1| < 1 / 4 x P2.

[0022] Effects of the invention

[0023] According to the present application, it is possible to provide a peep-type wide field of view image display device that is small (thin) and light, has excellent mass productivity, and has low manufacturing cost, and that enables a user to visually recognize a wide field of view (FOV of 80° or more) and a high-resolution image. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 FIG. 1 is a diagram showing the structure of a peep-type wide field of view image display device according to one embodiment.

[0025] Figure 2 FIG. 2 is a diagram illustrating a standard light path.

[0026] Figure 3 FIG. 3 is a diagram illustrating a direct light path that causes ghosting.

[0027] Figure 4is a diagram illustrating chief rays passing through the pupil surface SO and having an inclination θ with respect to the optical axis A.

[0028] Figure 5 is a diagram illustrating a structure table relating to the optical system of the wide field of view image display device of Embodiment 1.

[0029] Figure 6 is a diagram illustrating coefficients of the aspherical equation of Embodiment 1.

[0030] Figure 7 is a diagram illustrating a graph showing the relationship between the focal point shift and the absolute value of the OTF of Embodiment 1.

[0031] Figure 8 is a diagram illustrating a graph showing the relationship between the image surface curvature and the field of view angle and a graph showing the relationship between the distortion rate and the field of view angle of Embodiment 1.

[0032] Figure 9 is a diagram illustrating the structure of the wide field of view image display device of Embodiment 2.

[0033] Figure 10 is a diagram illustrating the standard light path of Embodiment 2.

[0034] Figure 11 is a diagram illustrating the direct light path in which ghosting occurs of Embodiment 2.

[0035] Figure 12 is a diagram illustrating chief rays passing through the pupil surface SO and having an inclination θ with respect to the optical axis A in Embodiment 2.

[0036] Figure 13 is a diagram illustrating a structure table relating to the optical system of the wide field of view image display device of Embodiment 2.

[0037] Figure 14 is a diagram illustrating coefficients of the aspherical equation of Embodiment 2.

[0038] Figure 15 is a diagram illustrating a graph showing the relationship between the focal point shift and the absolute value of the OTF of Embodiment 2.

[0039] Figure 16 is a diagram illustrating a graph showing the relationship between the image surface curvature and the field of view angle and a graph showing the relationship between the distortion rate and the field of view angle of Embodiment 2. DETAILED DESCRIPTION

[0040] Hereinafter, an embodiment of the present application will be described with reference to the drawings.

[0041] Figure 1 is a diagram illustrating the structure of the wide field of view image display device 1 of one embodiment. Figure 2This is a diagram illustrating a standard optical path.

[0042] Figure 1 The illustrated wide field of view image display device 1 is used by a user to Figure 1 The wide-field image display device 1 is a device for viewing from the left side of the user's eye. Furthermore, the wide-field image display device 1 can be provided for each of the user's right and left eyes, or for only one of the two. Furthermore, the wide-field image display device 1 can be applied to, for example, a VR HMD.

[0043] The wide-view image display device 1 includes, in order from the user's eye side, an eyepiece optical system OC, a circular polarization plate CP, and a display element D. The eyepiece optical system OC includes, in order from the user's eye side, a first lens L1 and a second lens L2.

[0044] The first surface S1 of the first lens L1, which faces the user's eye, is an aspherical surface. The second surface S2 of the first lens L1, which faces the display element D, is a flat or nearly flat surface. Furthermore, a reflective polarizing plate (reflective polarizing film) RP and a quarter-wave plate (quarter-wave film) QWP are laminated on the second surface S2 in this order, starting from the user's eye. The reflective polarizing plate RP is, for example, a wire grid polarizing plate or a cholesteric polarizing plate.

[0045] The third surface S3 of the second lens L2, which faces the user's eye, is an aspherical surface. The portion of the third surface S3 near the optical axis A of the eyepiece optical system OC is convex, projecting toward the user's eye. Alternatively, the portion of the third surface S3 near the optical axis A may be approximately flat. The fourth surface S4 of the second lens L2, which faces the display element D, is an aspherical surface. The fourth surface S4 is convex, projecting toward the display element D. Furthermore, the fourth surface S4 is coated with a half-mirror (semi-transmissive mirror) HM.

[0046] The circular polarizing plate CP is laminated on the display element D. Alternatively, the circular polarizing plate CP may be disposed in the space between the eyepiece optical system OC and the display element D (more specifically, between the half mirror HM and the display element D) instead of being laminated on the display element D. The circular polarizing plate CP is, for example, formed by laminating a quarter-wavelength plate on a linear polarizing plate.

[0047] The display element D includes an image display surface S5 for displaying images, a cover glass D1 for protecting the image display surface S5, and a display element substrate D2 for displaying images on the image display surface S5. The display element D is, for example, an OLED (Organic Light Emitting Diode) panel or a micro LED (Light Emitting Diode) panel with a wide viewing angle.

[0048] In the wide field of view image display device 1 of such a structure, the image light emitted from the display element D travels along the standard light path (including the light path of the return) exemplified by Figure 2 (and Figure 1 ) and is incident to the user's eye (pupil).

[0049] As exemplified by Figure 2 (and Figure 1 ), the image light emitted from the image display surface S5 of the display element D via the protection glass Dl first passes through the circularly polarizing plate CP. By this, the polarization state of the image light becomes a right-handed or left-handed circularly polarized state.

[0050] Subsequently, a part of the image light that has passed through the circularly polarizing plate CP is transmitted by the half mirror HM, and the rest is reflected by the half mirror HM to become useless light.

[0051] Subsequently, the image light that has transmitted the half mirror HM passes through the 2nd lens L2 in the order of the 4th surface S4 and the 3rd surface S3.

[0052] Subsequently, the image light that has passed through the 2nd lens L2 passes through the 1 / 4 wave plate QWP. By this, the polarization state of the image light changes from the right-handed or left-handed circularly polarized state to a linearly polarized state. Here, let the azimuth angle of this polarization plane be 0°.

[0053] Subsequently, the image light that has passed through the 1 / 4 wave plate QWP is reflected by the reflecting polarizing plate RP. Here, the reflecting polarizing plate RP reflects the light in the linearly polarized state with the azimuth angle of 0° and transmits the light in the linearly polarized state with the azimuth angle of 90°.

[0054] Subsequently, the image light that has been reflected by the reflecting polarizing plate RP passes through the 1 / 4 wave plate QWP again. By this, the polarization state of the image light changes from the linearly polarized state with the azimuth angle of 0° to a right-handed or left-handed circularly polarized state.

[0055] Subsequently, the image light that has passed through the 1 / 4 wave plate QWP passes through the 2nd lens L2 again in the order of the 3rd surface S3 and the 4th surface S4.

[0056] Subsequently, a part of the image light that has passed through the 4th surface S4 of the 2nd lens L2 is reflected by the half mirror HM, and the rest is transmitted by the half mirror HM to become useless light.

[0057] Subsequently, the image light that has been reflected by the half mirror HM passes through the 2nd lens L2 again in the order of the 4th surface S4 and the 3rd surface S3.

[0058] After that, the image light that has passed through the second lens L2 passes through the 1 / 4 wavelength plate QWP again. Due to this, the polarization state of the image light changes from a left-handed or right-handed circularly polarized state to a linearly polarized state with an azimuth angle of 90°.

[0059] After that, the image light that has passed through the 1 / 4 wavelength plate QWP transmits the reflective polarizing plate RP and passes through the first lens Ll in the order of the second surface S2, the first surface Sl. Then, the image light that has passed through the first lens Ll passes through the pupil surface SO and is incident on the user's eye (pupil). Note that the position of the pupil surface SO is also the position of the user's eye (pupil) that is assumed.

[0060] Further, in the wide field of view image display device 1, if the refractive power of the ocular optical system OC is P0, the refractive power of the first lens Ll is Pl, and the refractive power of the second lens L2 with respect to the image light that is emitted from the display element D and travels along the above-mentioned standard light path is P2, the relationship between P0 and P2 satisfies the following equation (1), and the relationship between Pl and P2 satisfies the following equation (2).

[0061] 0.8 x P0 < P2 < 1.2 x P0 Equation (1)

[0062] |Pl| < 1 / 4 x P2 Equation (2)

[0063] Further, in the case where the refractive power P2 of the second lens L2 is 0.06 (unit: 1 / mm) or less, if the refractive power of the third surface S3 is PW3, and the refractive power of the reflection toward the user's eye side by the half mirror HM coated on the fourth surface S4 is PW4R, the portion near the optical axis A in the third surface S3 of the second lens L2 is an approximate plane that satisfies the following equation (3).

[0064] |PW3| > -1 / 10 x PW4R Equation (3)

[0065] Further, the refractive power P0 (unit: 1 / mm) of the ocular optical system OC satisfies the following equation (4).

[0066] 0.05 < P0 < 0.075 Equation (4)

[0067] Further, if the maximum size of the image displayed on the image display surface S5 of the display element D is DD, and the effective diameter of the second lens L2 is ED, the relationship between DD and ED satisfies the following equation (5).

[0068] DD < 0.8 x ED Equation (5)

[0069] Further, DD is also the diameter of a circle circumscribing the display region of the image when the image is displayed on the image display surface S5. Further, ED is also the diameter of a circle circumscribing the region through which the light beam of the image projected to the user's eye (pupil) passes through the 2nd lens L2.

[0070] Further, it is preferable that the material of the 2nd lens L2 be a resin material satisfying the following equation (6) for the refractive index Nd and the following equation (7) for the Abbe number Vd.

[0071] Nd < 1.65 Equation (6)

[0072] Vd > 50 Equation (7)

[0073] Further, when the position of the pupil surface S0 is assumed to be a position 12 mm from the 1st surface S1 of the 1st lens L1 toward the user's eye side and the chief ray passing through the pupil surface S0 and having an inclination θ with respect to the optical axis A is inversely traced from the pupil surface S0 toward the 1st surface S1, the chief ray initially incident to the 3rd surface S3 of the 2nd lens L2 is inclined toward the direction away from the optical axis A in the advancing direction, and the chief ray emitted from the 4th surface S4 of the 2nd lens L2 is inclined toward the direction close to the optical axis A in the advancing direction.

[0074] For example, in the case where θ is 40°, if the incident angle of the chief ray initially incident to the 3rd surface S3 with respect to the 3rd surface S3 is assumed to be θ3, and the exit angle of the chief ray emitted from the 4th surface S4 with respect to the 4th surface S4 is assumed to be θ4, θ3 satisfies the following equation (8) and / or θ4 satisfies the following equation (9).

[0075] | θ3 | > 30° Equation (8)

[0076] | θ4 | > 30° Equation (9)

[0077] Hereinafter, the action and effect of the wide field of view image display device 1 of such a structure will be described in detail. Further, hereinafter, the inverse tracing of the light ray from the user's eye side toward the display element D side will be assumed as a premise unless specifically described.

[0078] In the wide field of view image display device 1, according to the satisfaction of the above equations (1) and (2), the 2nd lens L2 mainly bears a large part of the refractive power of the ocular optical system OC.

[0079] If attention is paid to the light path related to the 2nd lens L2 in the above-described standard light path (including the return light path), the refractive power P2 of the 2nd lens L2 can be approximately obtained by the following equation (10).

[0080] P2 ≒ PW4 + PW3_1 + PW3_2 + PW4R + PW3_3 Equation (10)

[0081] Here, the refractive power of each of the PW4, the PW3_l, the PW3_2, the PW4R, and the PW3_3 is as follows. Further, the PW3_l, the PW3_2, and the PW3_3 become the same value PW3.

[0082] The PW4 is a refractive power produced by refraction at the 4th surface S4 when image light that has passed through the circularly polarizing plate CP and has been transmitted by the half mirror HM is incident on the 4th surface S4.

[0083] The PW3_l is a refractive power produced by refraction at the 3rd surface S3 when image light that has been incident on the 4th surface S4 is emitted from the 3rd surface S3 through the half mirror HM.

[0084] The PW3_2 is a refractive power produced by refraction at the 3rd surface S3 when image light that has been reflected by the reflective polarizing plate RP and has passed through the 1 / 4 wave plate QWP is incident on the 3rd surface S3.

[0085] The PW4R is a refractive power produced by reflection at the half mirror HM when image light that has been incident on the 3rd surface S3 is reflected by the half mirror HM. This refractive power can be calculated using an optical formula by the following equation (11-3).

[0086] The PW3_3 is a refractive power produced by refraction at the 3rd surface S3 when image light that has been incident on the 4th surface S4 by reflection at the half mirror HM is emitted from the 3rd surface S3.

[0087] Further, the PW4 can be calculated using an optical formula by the following equation (11-1).

[0088] PW4 = (1 - Nd) x C4 Equation (11-1)

[0089] Here, Nd is the refractive index of the 2nd lens L2, and C4 is the curvature of the 4th surface S4.

[0090] The PW3_l, the PW3_2, and the PW3_3 become the same value PW3. This refractive power can be calculated using an optical formula by the following equation (11-2).

[0091] PW3 = (Nd - 1) x C3 Equation (11-2)

[0092] Here, C3 is the curvature of the 3rd surface S3.

[0093] The PW4R can be calculated using an optical formula by the following equation (11-3).

[0094] PW4R = -2 x Nd x C4 Equation (11-3)

[0095] The third surface S3 and the fourth surface S4 of the second lens L2 are both convex, and therefore each of the power elements on the right side of the above equation (10) has a positive value. Thus, the power that the second lens L2 needs to assume can be obtained by the combination of smaller power elements. Furthermore, as is apparent from a comparison between the above equation (11-1) and the above equation (11-3), the fourth surface S4 can have a particularly gentle curvature to produce the necessary PW4R.

[0096] As a result, the second lens L2 can be configured with a convex surface having a gentle curvature, and a large power that satisfies the above equations (1) and (4) can be produced, so that the generation of aberration can be suppressed to be small.

[0097] In addition, even if the second lens L2 is a lens of a material having a small refractive index Nd, the necessary power can be produced. Therefore, a material having a large Abbe number Vd, i.e., a small dispersion, can be selected as the material of the second lens L2. By selecting a material having a small dispersion, the generation of chromatic aberration of the second lens L2 can be suppressed to be low.

[0098] Specifically, the material of the second lens L2 is preferably selected from among materials included in the range that satisfies the above equations (6) and (7). Furthermore, by selecting a resin material that can be injection molded and is included in the range, the second lens L2 can be easily and inexpensively manufactured.

[0099] Furthermore, the third surface S3 of the second lens L2 and the first surface S1 of the first lens L1 are both aspherical and face the air, and therefore have a large aberration correction effect, and these surfaces can correct the aberration of the entire eyepiece optical system OC to a level that is practically sufficient.

[0100] In addition, in a case where the power P0 of the eyepiece optical system OC is 0.06 (unit: 1 / mm) or less, the power of the second lens L2 is substantially the same as the power P0 of the eyepiece optical system OC, i.e., the power required for the second lens L2 can also be 0.06 (unit: 1 / mm) or less. Furthermore, the size of this power can be reasonably produced by only the PW4R calculated from the above equation (11-3). In this case, as long as the above equation (3) is satisfied, the shape of the portion near the optical axis A in the third surface S3, which is aspherical, can be an approximate plane that is close to a plane.

[0101] In addition, since the power P2 of the second lens L2 has a positive value, the above equation (2) can be transformed into the following equation (12).

[0102] -1 / 4 x P2 < P1 < 1 / 4 x P2 Equation (12)

[0103] Further, in a case where the refractive power PI of the first lens LI has a positive value, the above equation (12) can be expressed as the following equation (13), and in a case where the refractive power PI of the first lens LI has a negative value, the above equation (12) can be expressed as the following equation (14).

[0104] P1<1 / 4 x P2 Equation (13)

[0105] -1 / 4 x P2 < PI Equation (14)

[0106] When the refractive power PO of the ocular optical system OC is increased in order to generate a large FOV from a small display element D, the focal length becomes short, and therefore, in order to secure a sufficient eye relief with respect to the ocular optical system OC and to secure a distance from the display element D, it is important to satisfy the above equations (13) and (14) as described below.

[0107] Since the FOV is large, the outer diameter (DLI) of the first lens LI, which can be estimated by the following equation (15), is large.

[0108] DLI ≒ 2 x eye relief x tan(FOV / 2) Equation (15)

[0109] Therefore, in a case where the first lens LI has a positive refractive power, if the refractive power PI of the first lens LI is increased, the central thickness needs to be increased greatly in order to secure the edge thickness. The increase in the thickness of the first lens LI has an effect of reducing the eye relief.

[0110] Further, according to the above equation (4), the focal length of the ocular optical system OC is short to less than 20 mm, and therefore, when the refractive power of the first lens LI exceeds a certain value, it is difficult to secure the eye relief.

[0111] In addition, as a balance of the refractive powers of the first lens LI and the second lens L2, if the refractive power of the first lens LI is increased and the refractive power of the second lens L2 is decreased, the back focal point position of the ocular optical system OC moves in the direction of the inside of the ocular optical system OC. Therefore, when the positive refractive power of the first lens LI with respect to the second lens L2 exceeds a certain limit, the back focal point position enters the inside of the ocular optical system OC. Since a virtual image needs to be projected to the far side, the image display surface S5 of the display element D needs to be disposed near the back focal point position of the ocular optical system OC. Therefore, in order to avoid physical interference, the back focal point position of the ocular optical system OC must be located at a position further outside the ocular optical system OC than the fourth surface S4 of the second lens L2 (the right side in the drawing). Figure 1 or Figure 2

[0112] ​On the other hand, in the case where the first lens Ll has a negative refractive power, the stronger the negative refractive power of the first lens Ll is, the larger the beam diameter of the image light passing through the second lens L2 is. Also, since the negative refractive power of the first lens Ll needs to be offset, the positive refractive power of the second lens L2 needs to be increased. Therefore, when the negative refractive power of the first lens Ll exceeds a certain limit, the image peripheral light which should be emitted toward the display element D through the second lens L2 can be totally reflected at the fourth surface S4 of the second lens L2.

[0113] Also, in the first lens Ll, the second surface S2 is a plane or an approximately plane, and the first surface Sl is an aspheric surface. In order to correct the tangential image surface curvature which is generated in the negative direction in the second lens L2, the curvature of the aspheric surface is strengthened toward the outer periphery in the negative direction, and thus, in a particularly large FOV, the outer periphery of the first surface Sl protrudes toward the user's eye side (see FIG. 6, for example). Figure 1 The stronger the negative refractive power of the first lens Ll is, the greater the amount of protrusion is, and the more likely it is to cause interference with the user's face.

[0114] The first surface Sl of the first lens Ll is an aspheric surface, and has an important role of offsetting the aberration generated in the second lens L2, but as described above, in the case where the refractive power thereof is not properly set, there is a problem that it is not possible to secure a sufficient eyebox and it is not possible to secure the distance between the second lens L2 and the display element D. However, by satisfying the above equations (13), (14), it is possible to avoid these problems.

[0115] Thus, the first lens Ll is thin, and the degree of reduction in the eyebox is small.

[0116] Also, in the wide field of view image display device 1, the second surface S2 of the first lens Ll is a plane or an approximately plane, and thus even if a reflective polarizing plate RP and a 1 / 4 wavelength plate QWP are stacked on this surface, it is possible to maintain the adhesion thereof well.

[0117] If the diameter of the stacked surface of the second surface S2 on which the reflective polarizing plate RP and the 1 / 4 wavelength plate QWP are stacked is DL, and the maximum value of the sag of the second surface S2 is SL, the second surface S2 which is a plane or an approximately plane is a plane, a spherical surface, or an aspheric surface which satisfies the following equation (16).

[0118] 0.05 x DL > |SL| Equation (16)

[0119] For example, even in the case where the 2nd surface S2 is a spherical surface and the maximum value of the sag is near the limit defined by the above formula (16), by stretching and contracting the size in the circumferential direction by about 0.6%, it is possible to laminate the reflective polarizing plate (reflective polarizing film) RP and the 1 / 4 wave plate (1 / 4 wave film) QWP to the 2nd surface S2. If the reflective polarizing plate (reflective polarizing film) RP and the 1 / 4 wave plate (1 / 4 wave film) QWP are those using a resin film as the base material, this degree of stretching and contraction is a reasonable value.

[0120] Further, in the wide field image display device 1, the above formula (5) is satisfied. As explained below, this contributes to the suppression of the generation of ghost images.

[0121] Figure 3 is an example of direct light. Direct light is light that exits from the display element D and passes through the pupil surface SO without reflecting once along the standard light path (i.e., not reflecting at all), and is stray light that causes ghost images. Figure 2 (And Figure 1 ) is an example of the standard light path (i.e., not reflecting at all), and is stray light that causes ghost images.

[0122] In the wide field image display device 1, the reflective polarizing plate RP and the 1 / 4 wave plate QWP that are laminated to the 2nd surface S2 of the 1st lens LI are used to shield (light block) such direct light, but if the 2nd lens L2 has a retardation, the light that exits from the display element D and passes through the circularly polarized plate CP in a circularly polarized state can have its polarization state destroyed when it passes through the 2nd lens L2, and the light blocking action of the reflective polarizing plate RP and the 1 / 4 wave plate QWP can not function adequately.

[0123] Therefore, the 2nd lens L2 is made of a material with small birefringence, and since the retardation is proportional to the birefringence and the optical path length, it is important to shorten the optical path length of the lens periphery portion that easily has a large birefringence due to internal stress and the like, and the 2nd lens L2 that has both the 3rd surface S3 and the 4th surface S4 in a convex shape is a shape that is suitable for this.

[0124] Further, as illustrated in Figure 3 , the direct light that exits from the display element D and passes through the eyepiece optical system OC without reflecting once and thereby passes through the pupil surface SO is converging light that exits from the display element D toward the eye side of the user, including subordinate light, and the size of the passing region in the 2nd lens L2 is smaller than the size of the image displayed on the image display surface S5.

[0125] Therefore, in the wide field image display device 1, by satisfying the above formula (5), the direct light that exits from the image display surface S5 and passes through the pupil surface SO is caused to pass through the 2nd lens L2 while avoiding the periphery portion where the birefringence is large.

[0126] Thus, the allowable amount of birefringence of the peripheral portion of the second lens L2 can be greatly relaxed. For the retardation, it is preferable that the central portion of the second lens L2 be 10 nm or less, and the peripheral portion can be several tens of nm or so.

[0127] The third surface S3 of the second lens L2 is an aspherical surface, and thus, if the productivity is taken into consideration, the manufacturing method is preferably molding. When molding is employed, thermal stress remains in the peripheral portion of the lens, and the tendency of the birefringence to increase due to the photoelastic effect is strong. However, if the above-described formula (5) is satisfied, not only glass but also a resin material having a small birefringence can be used to be manufactured by molding. As the resin material used at this time, for example, Optimas (registered trademark) of Mitsubishi Gas Chemical, AZP (registered trademark) published by Asahi Kasei in 2014, APEL (registered trademark) of Mitsui Chemical, and the like can be used.

[0128] In addition, these resin materials are all acrylic materials satisfying the above-described formulas (6) and (7).

[0129] Further, in the wide field of view image display device 1, the above-described formula (4) is satisfied.

[0130] Here, the reason why the power P0 of the ocular optical system OC is set to be less than 0.075 (unit: 1 / mm) is that a strong power can be generated with a single sphere for the second lens L2, but the stronger the power, the more the aberration increases, and in particular, when it exceeds 0.075 (unit: 1 / mm), the aberration significantly increases.

[0131] In addition, the reason why the power P0 of the ocular optical system OC is set to be greater than 0.05 (unit: 1 / mm) is that the smaller the power of the second lens L2, the better the state of the aberration becomes, but if the power of the ocular optical system OC is set to be 0.05 (unit: 1 / mm) or less, the left DD (the maximum size of the image displayed on the image display surface S5) in the above-described formula (5) becomes too large, and it is difficult to satisfy the above-described formula (5).

[0132] In addition, in the wide field of view image display device 1, the relationship between the focal length and the FOV in the case of the image distortion is as shown in the following formula (17).

[0133] EFL = (DD / 2) / {(1 + Dis / 100) x tan(FOV / 2)} Formula (17)

[0134] Here, EFL is the focal length of the ocular optical system OC.

[0135] Dis (unit: %) is the distortion rate at the image edge portion of the ocular optical system OC, which is defined by the following formula (18).

[0136] Dis = (actual maximum image height - ideal maximum image height) / (ideal maximum image height) × 100 Formula (18)

[0137] FOV is the field of view of the eyepiece optical system OC.

[0138] As described above, DD is the maximum size of the image displayed on the image display surface S5. DD / 2 is the image height of the image.

[0139] An optical equation that holds true in an optical system without image distortion is expressed as the following equation (19).

[0140] Ideal image height = focal length × tan(angle of view) Formula (19)

[0141] The relationship between the actual image height and the ideal image height when image distortion exists is expressed by the following equation (20).

[0142] Actual image height = (1 + Dis / 100) × ideal image height (20)

[0143] The following formula (21) can be derived from the above formulas (19) and (20).

[0144] Actual image height = focal length × tan(angle of view) × (1 + Dis / 100) Formula (21)

[0145] The above formula (17) can be derived by transforming the above formula (21).

[0146] The relationship between the refractive power P0 of the eyepiece optical system and image distortion is expressed as in the following equation (22) using the above equation (17).

[0147] P0=1 / EFL={(1+Dis / 100)×tan(FOV / 2)} / (DD / 2) Formula (22)

[0148] When comparing eyepiece optical systems with the same FOV, an eyepiece optical system with a negative Dis can reduce the refractive power of the eyepiece optical system compared to an eyepiece optical system without Dis. For example, if Dis is -30%, the refractive power of the eyepiece optical system can be reduced by 30% compared to a system without Dis.

[0149] In the wide-view image display device 1 , the refractive power of the eyepiece optical system OC is substantially equal to the refractive power of the second lens L2 , and therefore it can be said that the refractive power of the second lens L2 can be reduced by approximately 30%.

[0150] As described above, the 2nd lens L2 generates a strong refractive power, but since the stronger the refractive power, the more the aberration increases, in order to seek excellent resolving performance, it is preferable that the refractive power of the 2nd lens L2 be small. In particular, if the refractive power of the 2nd lens L2 is 0.075 (unit: 1 / mm) or more, the aberration significantly becomes large.

[0151] That is, the negative Dis is capable of maintaining the FOV and realizing the ocular optical system OC with higher resolving performance. In other words, the negative Dis is capable of maintaining the resolving performance and realizing the ocular optical system OC with a larger FOV.

[0152] Further, in the wide field image display device 1, as described above, the position of the pupil face SO is assumed to be a position of 12 mm from the 1st face SI of the 1st lens LI, and when the chief ray passing through the pupil face SO and having the inclination θ with respect to the optical axis A is inversely traced from the pupil face SO toward the 1st face SI, the chief ray initially incident to the 3rd face S3 of the 2nd lens L2 is inclined toward a direction away from the optical axis A in the proceeding direction, and the chief ray emitted from the 4th face S4 of the 2nd lens L2 is inclined toward a direction close to the optical axis A in the proceeding direction.

[0153] Figure 4 is a diagram illustrating the chief ray passing through the pupil face SO and having the inclination θ with respect to the optical axis A.

[0154] As Figure 4 illustrated as above, when the chief ray is inversely traced from the pupil face SO toward the 1st lens LI, the chief ray CR4 emitted from the 4th face S4 of the 2nd lens L2 is inclined toward a direction close to the optical axis A in the proceeding direction, and the 4th face S4 is a convex shape protruding toward the display element D side, so the exit angle θ4 at which the chief ray CR4 is emitted from the 4th face S4 has a large angle in the clockwise direction. Therefore, in the 4th surface S4, a large negative spherical aberration is generated in the chief ray. Also, the chief ray CR3 initially incident to the 3rd face S3 of the 2nd lens is inclined toward a direction away from the optical axis A in the proceeding direction, and the portion near the optical axis A in the 3rd face S3 is a convex shape protruding toward the user's eye side or an approximate plane, so the incident angle θ3 at which the chief ray CR3 is incident to the 3rd face S3 has an angle in the clockwise direction. Also, therefore, in the 3rd surface S3, a negative spherical aberration is generated in the chief ray. In particular, in the case where the 3rd face S3 is a convex shape protruding toward the user's eye side, the incident angle θ3 becomes large, and a large negative spherical aberration is generated.

[0155] Thus, when a negative spherical aberration is generated at the second lens L2 in the chief ray that has been traced inversely from the pupil plane SO toward the first lens Ll, for example, the height of the chief ray that is emitted from the pupil plane SO at an inclination angle (θ = 40°) of 40° and passes through the image display surface S5 of the display element D can be reduced. That is, the function of generating a negative Dis is performed. As described above, this is preferable in terms of designing an ocular optical system OC that has a large FOV while maintaining resolution performance.

[0156] In this case, by satisfying the above-described equations (8) and / or (9), the refractive power of the second lens L2 can be suppressed to less than 0.075 (unit: 1 / mm), and a sufficient negative Dis can be generated that enables design of a FOV exceeding 80°.

[0157] Further, the reason for assuming the position of the pupil plane SO to be 12 mm from the first surface Sl of the first lens Ll is that if the position of the pupil plane SO changes, θ3 and θ4 change, and thus in order to quantitatively define θ3 and θ4, the position of the pupil plane SO needs to be assumed. Generally, eyeglasses are adjusted so that the distance between the eye and the eyeglass lens is 12 mm. This is to prevent contamination of the eyeglass lens by tears generated by blinking. In the wide field image display device 1 as well, it is preferable to expand the distance between the ocular optical system OC and the eye to 12 mm or more.

[0158] As described above, in the wide field image display device 1 of one embodiment, the third surface S3 of the second lens L2 has a convex shape or an approximately planar shape, the fourth surface S4 has a convex shape, and the positive refractive power element having substantially five surfaces formed by polarization and reflection (see the above-described equation (10)). Thus, in the second lens L2, a relatively strong positive refractive power can be formed in the convex surface in which the curvature is moderated, and generation of aberration can be suppressed. Further, since a material having a low refractive index is used to produce a sufficiently strong positive refractive power, a material having a low dispersion can be selected, and generation of chromatic aberration can be suppressed.

[0159] Further, the first surface Sl of the first lens Ll and the third surface S3 of the second lens L2 are aspheric surfaces facing air. In the case of facing air, the refractive index difference at the interface is large, and thus even if the first surface Sl and the third surface S3 are relatively moderate aspheric shapes, aberration can be strongly corrected. Thus, an ocular optical system OC having excellent resolution performance can be designed, and the sag can be reduced to thin the ocular optical system OC.

[0160] Further, the third surface S3 and the fourth surface S4 of the second lens L2 each have a convex shape, whereby a large incident angle θ3 and an exit angle θ4 of chief rays are obtained, and a negative image distortion is generated at the time of inverse tracing. Thus, the refractive power of the second lens L2 can be suppressed, and an image with a large FOV can be projected from a display element D having a small image display surface size. Further, the image display surface size can be designed to be smaller than the outer diameter of the second lens L2. Further, stray light directly traveling within the ocular optical system OC avoids the lens periphery portion where a large birefringence is likely to occur and travels within the second lens L2, and thus the allowable amount of birefringence of the outer periphery portion of the second lens L2 can be increased, and the second lens L2 can be manufactured by molding of resin. By molding, even an aspherical lens can be manufactured at low cost.

[0161] Further, by performing distribution of the refractive powers of the first lens L1 and the second lens L2, a sufficient eyebox can be ensured, and a design avoiding a buffer between the ocular optical system OC and the display element D can be performed.

[0162] Thus, in the wide field of view image display device 1 of one embodiment, a user can visually recognize an image with a wide field of view (FOV of 80° or more) and high resolution, and effects such as a small (thin) and light weight, excellent mass productivity, and low manufacturing cost can be obtained.

[0163] Hereinafter, as specific examples of the wide field of view image display device 1 of one embodiment, a case where the portion near the optical axis A in the third surface S3 of the second lens L2 is a convex shape protruding toward the user's eye side will be described as Embodiment 1, and a case where the portion near the optical axis A in the third surface S3 of the second lens L2 is an approximately planar shape will be described as Embodiment 2. Further, in the structure table shown in each of the embodiments, consecutive numbers are attached in the direction of the optical path of the image light in reverse. Further, in each of the embodiments, optical specifications and data relating to performance are results obtained in reverse along the optical path in accordance with the reversibility principle of light. Further, in each of the embodiments, the material of the second lens L2 is Optimas (registered trademark) 7500 of Mitsubishi Gas Chemical Company, Inc.

[0164] <Embodiment 1>

[0165] In the wide field of view image display device 1 of Embodiment 1, the structure, the standard optical path, the direct light path in which ghosting occurs, and the chief ray passing through the pupil S0 and having an inclination θ (40°) with respect to the optical axis A are the same as those shown in Embodiment 1. Figure 1 、 Figure 2 、 Figure 3 and Figure 4 .

[0166] Figure 5is a drawing illustrating a structure table relating to the optical system of the wide field image display device 1 of Embodiment 1. Figure 6 is a drawing illustrating coefficients of the aspherical equation of Embodiment 1.

[0167] Figure 5 The illustrated structure shows the type of surface, the radius of curvature on the optical axis A, the thickness on the optical axis A, the material (Nd, Vd), and the effective diameter corresponding to each consecutive number. The sag of each aspherical surface can be found by the aspherical equation of the following formula (23).

[0168] Sag = (Y2 / R) / [1+SQRT{1-(1+k) x (Y / R)2}]+a x Y2+b x Y4+c x Y6+d x Y8+e x Y10 Formula (23)

[0169] Here, Y (unit: mm) is the distance from the optical axis A. R (unit: mm) is the radius of curvature on the optical axis A.

[0170] Sag (unit: mm) is the coordinate in the direction of the optical axis A of the portion of the aspherical surface having a distance Y from the optical axis when the point of the aspherical surface on the optical axis is taken as the origin.

[0171] The coefficients k, a, b, c, d, and e for each aspherical surface are as shown in Figure 6 .

[0172] Further, in the wide field image display device 1 of Embodiment 1, P0, P1, P2, PW3, and PW4R are as follows.

[0173] P0: 0.0624 (unit: 1 / mm)

[0174] P1: 0.0062 (unit: 1 / mm)

[0175] P2: 0.0608 (unit: 1 / mm)

[0176] PW3: 0.013161 (unit: 1 / mm)

[0177] PW4R: 0.031616 (unit: 1 / mm)

[0178] Here,

[0179] P2 = 0.97 x P0,

[0180] |P1| = 0.10 x P2,

[0181] the above formulas (1), (2) are satisfied, and the above formula (4) is also satisfied.

[0182] In addition, the material of the second lens L2 is Optimas (registered trademark) 7500 by Mitsubishi Gas Chemical Company, Inc., and satisfies the above-described equations (6) and (7).

[0183] In addition, in the wide field of view image display device 1 of Embodiment 1, FOV, DD, Dis, θ3, and θ4 are as follows.

[0184] FOV: 80°

[0185] DD: 22.8 mm

[0186] Dis: -30%

[0187] θ3: 42.9°

[0188] θ4: 35.3°

[0189] Here, DD is 22.8 mm, and the effective diameter of the second lens L2 according to the structure table shown in Table 1 also satisfies the above-described equation (5). Figure 5

[0190] In addition, θ3 is 42.9° and θ4 is 35.3°, and thus the above-described equations (8) and (9) are also satisfied.

[0191] In Figure 7 the graph showing the relationship between the focal point movement and the absolute value of the OTF (Optical Transfer Function) is exemplified in Embodiment 1, and the performance of the eyepiece optical system OC is shown, in Figure 8 the graph showing the relationship between the image surface curvature and the field of view angle and the graph showing the relationship between the distortion rate and the field of view angle are exemplified in Embodiment 1. In addition, Figure 7 The exemplified graphs are graphs in the case where the spatial frequency is 40 cycles / mm, the wavelength is 525 μm, the pupil diameter is 4 mm, and the pupil position is 15 mm. Figure 8 The exemplified graphs are graphs in the case where the pupil position is 15 mm. Any of the graphs shows that the resolution performance of the eyepiece optical system OC of Embodiment 1 is good.

[0192] <Embodiment 2>

[0193] Figure 9 is a diagram of the structure of the wide field of view image display device 1 of Embodiment 2. Figure 10 is a diagram exemplifying the standard light path of Embodiment 2. Figure 11 is a diagram exemplifying the direct light path in which ghosting occurs of Embodiment 2. Figure 12 is a diagram exemplifying the chief ray passing through the pupil surface SO and having an inclination θ with respect to the optical axis A in Embodiment 2.

[0194] ​In the wide field image display device 1 of Embodiment 2, as Figure 9 illustrated, the portion near the optical axis A in the third surface S3 of the second lens L2 is an approximate plane. In addition, the standard light path is Figure 10 the light path illustrated in Figure 9 ( and Figure 11 ). The direct light path in which ghost is generated is the light path illustrated in Figure 12 . In addition, the chief ray passing through the pupil surface SO and having an inclination θ (40°) with respect to the optical axis A is the chief ray illustrated in

[0195] Figure 13 is a diagram illustrating a structure table relating to the optical system of the wide field image display device 1 of Embodiment 2. Figure 14 is a diagram illustrating the coefficients of the aspherical equation of Embodiment 2.

[0196] In the structure table illustrated in Figure 13 , the sag of each aspherical surface can be found by the aspherical equation of the above-described formula (23).

[0197] Here, the coefficients k, a, b, c, d, and e of each aspherical surface are as shown in Figure 14 .

[0198] In addition, in the wide field image display device 1 of Embodiment 2, P0, P1, P2, PW3, and PW4R are as follows.

[0199] P0: 0.0542 (unit: 1 / mm)

[0200] P1: 0.0081 (unit: 1 / mm)

[0201] P2: 0.0510 (unit: 1 / mm)

[0202] PW3: 0.001976 (unit: 1 / mm)

[0203] PW4R: 0.044283 (unit: 1 / mm)

[0204] Here,

[0205] P2 = 0.94 x P0,

[0206] |P1| = 0.16 x P2,

[0207] the above-described formulas (1) and (2) are satisfied, and the above-described formula (4) is also satisfied.

[0208] Further, in this case, P2 is 0.06 (unit: 1 / mm) or less, and according to the values of PW3 and PW4R, the portion in the 3rd surface S3 near the optical axis A is an approximate plane satisfying the above-described formula (3).

[0209] Further, the material of the 2nd lens L2 is also Optimas (registered trademark) 7500 of Mitsubishi Gas Chemical Company, Inc. in the same manner as in Embodiment 1, and satisfies the above-described formulas (6) and (7).

[0210] Further, in the wide field of view image display device 1 of Embodiment 2, FOV, DD, Dis, θ3, and θ4 are as follows.

[0211] FOV: 80°

[0212] DD: 12.0 mm

[0213] Dis: -24%

[0214] θ3: 38.4°

[0215] θ4: 28.3°

[0216] In this case, DD is 12.0 mm, and according to the effective diameter of the 2nd lens L2 of the structure table exemplified in Figure 13 the above-described formula (5) is satisfied.

[0217] Further, θ3 is 38.4° and θ4 is 28.3°, and although the above-described formula (9) is not satisfied, the above-described formula (8) is satisfied.

[0218] In Figure 15 a graph showing the relationship between the focal point movement and the absolute value of the OTF is exemplified in Embodiment 2, and the performance of the ocular optical system OC of Embodiment 2 is shown in the graph. Figure 16 a graph showing the relationship between the image surface curvature and the field of view angle and a graph showing the relationship between the distortion rate and the field of view angle are exemplified in Embodiment 2. Further, Figure 15 The exemplified graph is a graph in a case where the spatial frequency is 40 cycles / mm, the wavelength is 525 μm, the pupil diameter is 4 mm, and the pupil position is 15 mm. Figure 16 The exemplified graph is a graph in a case where the pupil position is 15 mm. Any of the graphs shows that the resolution performance of the ocular optical system OC of Embodiment 2 is good.

[0219] The above, the present application is not directly limited to the above-described embodiments, and in the implementation stage, the structural elements can be deformed and embodied within the scope not departing from the gist thereof. Further, by the appropriate combination of the plurality of structural elements disclosed by the above-described embodiments, various applications can be formed. For example, it is also possible to delete several structural elements among all the structural elements shown in the embodiments. Also, it is also possible to appropriately combine the structural elements in different embodiments.

[0220] Explanations of reference numerals

[0221] 1 wide field image display device

[0222] OC ocular optical system

[0223] CP circularly polarizing plate

[0224] A optical axis

[0225] D display element

[0226] D1 protective glass

[0227] D2 display element substrate

[0228] L1 first lens

[0229] L2 second lens

[0230] RP reflective polarizing plate

[0231] QWP 1 / 4 wave plate

[0232] HM half mirror

[0233] S0 pupil

[0234] S1 first surface

[0235] S2 second surface

[0236] S3 third surface

[0237] S4 fourth surface

[0238] S5 image display surface

[0239] CR3, CR4 chief ray

Claims

1. A wide field of view image display device which is a peep type wide field of view image display device, characterized by comprising, in order from the eye side of a user, an eyepiece optical system, a circularly polarizing plate, and a display element, the eyepiece optical system includes, in order from the eye side of the user, a first lens and a second lens, a first surface in the first lens which is a surface on the eye side of the user is an aspherical surface, a second surface in the first lens which is a surface on the display element side is a flat surface or an approximately flat surface, and a reflection polarizing plate and a 1 / 4 wave plate are laminated in order from the eye side of the user on the second surface, a third surface in the second lens which is a surface on the eye side of the user is an aspherical surface, and a portion near an optical axis of the eyepiece optical system in the third surface is a convex shape which is convex toward the eye side of the user or an approximately flat surface, and a curvature of an outer peripheral portion of the third surface is smaller than a curvature of the portion near the optical axis, a fourth surface in the second lens which is a surface on the display element side is an aspherical surface which is convex toward the display element side, and a half mirror is coated on the fourth surface, if a refractive power of the eyepiece optical system is P0, a refractive power of the first lens is PI, and a refractive power of the second lens with respect to image light which is emitted from the display element and travels along a standard light path is P2, then: 0.8 x P0 < P2 < 1.2 x P0, | PI | < 1 / 4 x P2.

2. The wide field of view image display device according to claim 1, characterized in that the circularly polarizing plate is laminated to the display element, or the circularly polarizing plate is disposed in a space between the eyepiece optical system and the display element.

3. The wide field of view image display device according to claim 1 or 2, characterized in that if a maximum size of an image displayed on a display surface of the display element is DD, and an effective diameter of the second lens is ED, then: DD < 0.8 x ED.

4. The wide field of view image display device according to claim 1 or 2, characterized in that a refractive index Nd and an Abbe number Vd of the second lens are: Nd < 1.65, Vd > 50.

5. The wide field of view image display device according to claim 4, characterized in that a material of the second lens is a resin material.

6. The wide field of view image display device according to claim 1 or 2, characterized in that a refractive power P0 of the eyepiece optical system is: 0.05 < P0 < 0.075, a unit of P0: 1 / mm.

7. The wide field of view image display device according to claim 1 or 2, characterized in that when a position of a pupil surface is assumed to be a position 12 mm from the first surface toward the eye side of the user, and a chief ray which passes through the pupil surface and has an inclination θ with respect to the optical axis is traced backward from the pupil surface toward the first surface, the chief ray which first enters the third surface is inclined toward a direction away from the optical axis in a traveling direction, and the chief ray which is emitted from the fourth surface is inclined toward a direction close to the optical axis in the traveling direction. ​ 8. The wide field of view image display device according to claim 7, wherein when the θ is 40°, if an incident angle of the chief ray initially incident to the 3rd face with respect to the 3rd face is θ3, and an exit angle of the chief ray emitted from the 4th face with respect to the 4th face is θ4, then: |θ3| > 30° and / or |θ4| > 30°.

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