Optical system and imaging apparatus

Abstract

To provide a small-sized optical system that has high optical performance in a wide focus range, and an imaging apparatus.SOLUTION: An optical system (OS1) has a first refractive lens (L1), a first transmission and reflection surface (HM1), a 1 / 4 wavelength plate (QWP), and a second transmission and reflection surface (HM2), which are arranged in order from an object side to an image side. In focusing, the first transmission and reflection surface moves in an optical axis direction. In focusing, the first refractive lens does not move, or the interval in the optical axis direction between the first transmission and reflection surface and the first refractive lens changes. The first refractive lens is separated from both the first transmission and reflection surface and the second transmission and reflection surface.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to an optical system and an imaging device. [Background technology]

[0002] In recent years, the importance of miniaturizing optical systems has increased due to the spread of smartphones and the shift from single-lens reflex cameras to mirrorless cameras in the high-end camera market. Patent Document 1 discloses a compact optical system (polarized reflective imaging system) equipped with a polarizing element and a half mirror. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2005-352273 A Summary of the Invention [Problem to be solved by the invention]

[0004] The optical system disclosed in Patent Document 1 has a dark F-number of 2.85. Because the polarized reflective imaging system has a structure in which the amount of light is 1 / 8 when randomly polarized light is incident, it is necessary to make the F-number brighter than that of a normal optical system. In addition, the optical system disclosed in Patent Document 1 does not have good aberrations during focusing and cannot increase the shooting magnification, so it is not possible to achieve high optical performance over a wide focusing range.

[0005] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide a compact optical system having high optical performance over a wide focus range. [Means for solving the problem]

[0006] An optical system according to one aspect of the present invention has, arranged in order from the object side to the image side, a first refractive lens, a first transmitting-reflecting surface, a quarter-wave plate, and a second transmitting-reflecting surface, wherein, during focusing, the first transmitting-reflecting surface moves in the optical axis direction, and, during focusing, the first refractive lens does not move or the distance between the first transmitting-reflecting surface and the first transmitting-reflecting surface in the optical axis direction changes, and the first refractive lens is separated from both the first transmitting-reflecting surface and the second transmitting-reflecting surface.

[0007] Other objects and features of the present invention are illustrated in the following examples. Effect of the Invention

[0008] According to the present invention, it is possible to provide a compact optical system having high optical performance over a wide focus range. [Brief description of the drawings]

[0009] [Figure 1] FIG. 2 is a schematic diagram showing an optical path of an optical system in each embodiment. [Diagram 2] FIG. 2 is a schematic diagram showing an optical path of an optical system in each embodiment. [Diagram 3] FIG. 2 is a cross-sectional view of an optical system in the first embodiment. [Figure 4] 4A to 4C are aberration diagrams of the optical system in Example 1. [Diagram 5] FIG. 11 is a cross-sectional view of an optical system in Example 2. [Figure 6] 10A to 10C are aberration diagrams of the optical system in Example 2. [Figure 7] FIG. 11 is a cross-sectional view of an optical system according to a third embodiment. [Figure 8] 11A to 11C are aberration diagrams of the optical system in Example 3. [Figure 9] FIG. 11 is a cross-sectional view of an optical system in Example 4. [Figure 10] 11A to 11C are aberration diagrams of the optical system in Example 4. [Figure 11] FIG. 13 is a cross-sectional view of an optical system in Example 5. [Figure 12]13A to 13C are aberration diagrams of the optical system in Example 5. [Figure 13] FIG. 13 is a cross-sectional view of an optical system in Example 6. [Figure 14] 13A to 13C are aberration diagrams of the optical system in Example 6. [Figure 15] FIG. 13 is a cross-sectional view of an optical system in Example 7. [Figure 16] 13A to 13C are aberration diagrams of the optical system in Example 7. [Figure 17] FIG. 13 is a cross-sectional view of an optical system in Example 8. [Figure 18] 13A to 13C are aberration diagrams of the optical system in Example 8. [Figure 19] FIG. 13 is a cross-sectional view of an optical system in Example 9. [Figure 20] 13A to 13C are aberration diagrams of the optical system in Example 9. [Figure 21] FIG. 23 is a cross-sectional view of an optical system in Example 10. [Figure 22] 13A to 13C are aberration diagrams of the optical system in Example 10. [Diagram 23] FIG. 21 is a cross-sectional view of an optical system in Example 11. [Figure 24] 13A to 13C are aberration diagrams of the optical system in Example 11. [Diagram 25] FIG. 23 is a cross-sectional view of an optical system in Example 12. [Figure 26] 13A to 13C are aberration diagrams of the optical system in Example 12. [Figure 27] FIG. 23 is a cross-sectional view of an optical system in Example 13. [Figure 28] 13A to 13C are aberration diagrams of the optical system in Example 13. [Figure 29] FIG. 23 is a cross-sectional view of an optical system in Example 14. [Diagram 30] 21A to 21C are aberration diagrams of the optical system in Example 14. [Diagram 31] FIG. 23 is a cross-sectional view of an optical system in Example 15. [Diagram 32] 15A to 15C are aberration diagrams of the optical system in Example 15. [Diagram 33] FIG. 21 is a cross-sectional view of an optical system in Example 16. [Diagram 34]21A to 21C are aberration diagrams of the optical system in Example 16. [Diagram 35] FIG. 21 is a cross-sectional view of an optical system in Example 17. [Diagram 36] 21A to 21C are aberration diagrams of the optical system in Example 17. [Figure 37] FIG. 23 is a cross-sectional view of an optical system in Example 18. [Figure 38] 21A to 21C are aberration diagrams of the optical system in Example 18. [Figure 39] FIG. 23 is a cross-sectional view of an optical system in Example 19. [Diagram 40] 21A to 21C are aberration diagrams of the optical system in Example 19. [Diagram 41] FIG. 23 is a cross-sectional view of an optical system in Example 20. [Diagram 42] 23A to 23C are aberration diagrams of the optical system in Example 20. [Diagram 43] FIG. 23 is a cross-sectional view of an optical system in Example 21. [Diagram 44] 23A to 23C are aberration diagrams of the optical system in Example 21. [Diagram 45] FIG. 23 is a cross-sectional view of an optical system in Example 22. [Figure 46] 23A to 23C are aberration diagrams of the optical system in Example 22. [Figure 47] FIG. 23 is a cross-sectional view of an optical system in Example 23. [Figure 48] 23A to 23C are aberration diagrams of the optical system in Example 23. [Figure 49] FIG. 23 is a cross-sectional view of an optical system in Example 24. [Figure 50] 23A to 23C are aberration diagrams of the optical system in Example 24. [Figure 51] FIG. 25 is a cross-sectional view of an optical system in Example 25. [Figure 52] 23A to 23C are aberration diagrams of the optical system in Example 25. [Diagram 53] FIG. 23 is a cross-sectional view of an optical system in Example 26. [Figure 54] 23A to 23C are aberration diagrams of the optical system in Example 26. [Figure 55] FIG. 2 is a schematic diagram of an imaging device including an optical system in each embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0011] The optical system (imaging optical system) of each embodiment forms an image of an object on an image plane, and obtains an image by arranging an image sensor, a photosensitive film, or the like on the image plane, thereby capturing an image. The optical system of each embodiment has a first refractive lens L1, a first transmission-reflection surface HM1, a quarter-wave plate QWP, and a second transmission-reflection surface HM2, which are arranged in this order from the object side to the image side. Light incident from the object side passes through the first transmission-reflection surface HM1 and the quarter-wave plate QWP in this order, and is reflected by the second transmission-reflection surface HM2. The light then passes through the quarter-wave plate QWP, is reflected by the first transmission-reflection surface HM1, passes through the quarter-wave plate QWP and the second transmission-reflection surface HM2, and is incident on an imaging surface IM such as an image sensor or a photosensitive film.

[0012] Here, the first transmission-reflection surface HM1 and the second transmission-reflection surface HM2 do not need to have a transmittance of 50% and a reflectance of 50%. The ratio of the transmittance to the reflectance for randomly polarized light is preferably in the range of 1:3 to 3:1. Randomly polarized light is light with Stokes parameters S0=1, S1=S2=S3=0. Furthermore, the first transmission-reflection surface HM1 and the second transmission-reflection surface HM2 may each be configured to absorb a portion of light. Furthermore, a lens (glass or resin) may be formed or bonded to both sides or one side of at least one of the first transmission-reflection surface HM1 or the second transmission-reflection surface HM2.

[0013] As the quarter-wave plate QWP, for example, a crystal having birefringence, a polymer film, or a liquid crystal alignment layer can be used. Also, a laminate of such crystals, polymer films, or liquid crystal alignment layers can be used. By appropriately laminating, a phase difference close to a quarter of the wavelength can be obtained in a wide wavelength range. For example, "WA-140T" by Nippon Kayaku Co., Ltd. or "Polar Correct" by Color Link Japan Co., Ltd. can be used. Note that the quarter-wave plate QWP is not limited to the above, and may be one using, for example, a sub-wavelength structure or a meta-structure. Specifically, for example, an inorganic wave plate by Dexerials Corporation or a product name "Nanoable Waveplate" by ENEOS Corporation can be used.

[0014] The quarter-wave plate QWP can be arranged, for example, by bonding with the first transmission-reflection surface HM1 or the second transmission-reflection surface HM2. The quarter-wave plate QWP can also be arranged separately from each transmission-reflection surface. For example, the film may be inserted into the optical path as it is, or the film bonded to a glass plate may be inserted into the optical path. A lens may be formed or bonded on both sides or one side of the quarter-wave plate QWP. For example, a lens may be molded on one or both sides of the inorganic wave plate using wafer-level optics technology with an inorganic wave plate as a substrate.

[0015] In an optical system with such a configuration, the image quality decreases when the entire system is extended (focusing is performed by moving all lenses back and forth along the optical axis by the same amount). The focusing range generally expected of a photographic lens is from infinity to more than 0.1 times, and it is preferable that focusing can be performed at least in this range and that the image quality is high. It is even more preferable that focusing can be performed up to a higher magnification. In each embodiment, changing the focusing position is called focusing. Furthermore, the direction in which optical elements such as lenses and transmissive / reflective surfaces are moved during focusing is along the optical axis unless otherwise specified, and the description "in the direction along the optical axis" may be omitted. Furthermore, in general, the larger the aperture of an optical system, the more difficult it becomes to maintain high image quality over a wide range of photographing magnifications. The optical systems of each embodiment achieve high image quality over a wide range of photographing magnifications despite their large apertures.

[0016] The optical system of each embodiment is an imaging optical system capable of changing the focal position by moving the first transmission-reflection surface HM1 back and forth in the optical axis direction. The optical system of each embodiment has a refractive lens that does not move or the relative distance with the first transmission-reflection surface HM1 changes when the focal position is changed, and is not integrated with either the first transmission-reflection surface HM1 or the second transmission-reflection surface HM2 (separate from each transmission-reflection surface). The refractive lens does not include optical elements that are parallel or nearly parallel plates, such as protective filters, sensor protection glasses, IR cut filters, UV cut filters, and low-pass filters. An example of a refractive lens that is not a nearly parallel plate is a spherical lens, for example, a lens in which the absolute value of the radius of curvature of at least one surface is smaller than 1 / 20 of the focal length of the entire optical system. The term "integrated" here means that the lenses are joined together (it does not matter if another lens is sandwiched between them), and "not integrated" means that there is an air gap between them.

[0017] In this way, by independently moving the first transmission-reflection surface HM1 during focusing, high image quality can be achieved over a wide focus range. By moving the reflection surface with high aberration correction capability, high image quality can be achieved over a wide focus range. As in each numerical example described later, the first transmission-reflection surface HM1 may be a flat surface. In this case, even if the first transmission-reflection surface HM1 is moved with focusing and the second transmission-reflection surface HM2 is not moved, high image quality can be achieved. This is due to the following reasons. For example, when the first transmission-reflection surface HM1 is moved forward, the distance between the first transmission-reflection surface HM1 and the second transmission-reflection surface HM2 increases. This is equivalent to extending the optical path length from the point where the light beam is reflected by the second transmission-reflection surface HM2 to the image surface, and moving the second transmission-reflection surface HM2 with high aberration correction capability in a pseudo manner. Therefore, even if the first transmission-reflection surface HM1 does not have power, the second transmission-reflection surface can be moved in a pseudo manner by moving the second transmission-reflection surface HM2, and high image quality can be achieved over a wide focus range.

[0018] In addition, when moving an optical element for focusing, a space is required for the movement. The first transmissive reflecting surface HM1 is suitable as a group to be moved when focusing because it is easy to secure this space on the object side. On the other hand, if it is considered that only the second transmissive reflecting surface HM2 is moved, it is difficult to secure this space. As in each numerical example described later, the second transmissive reflecting surface HM2 is preferably shaped or flat so as to be concave toward the object side. In this case, when focusing from infinity to a close distance, the second transmissive reflecting surface HM2 often needs to move toward the image side. When a long back focus is required, such as a lens for an interchangeable lens camera, it is necessary to prepare a space that cannot be used on the image side of the second transmissive reflecting surface HM2. Even if the back focus can be shortened, it is difficult to secure a space sufficient for focusing. This is because it is desirable to arrange a refractive lens on the image side of the second transmissive reflecting surface HM2 to correct the image surface or to increase the light-gathering power and increase the Fno.

[0019] In the optical system of each embodiment, when the refractive power on the object side of the first transmitting-reflecting surface HM1 is φfr and the power of the optical system (total) is φtotal, it is preferable to satisfy the following conditional expression (1). -1.00≦φfr / φtotal≦0.42 (1) In the optical system of each embodiment, the reflecting surface has the greatest aberration correction ability of the entire system. The reflecting surface has a Petzval sum with the opposite sign to the power of the reflecting surface, and does not generate chromatic aberration. How to effectively utilize this reflecting surface is important in achieving high image quality over a wide focus range despite the large aperture.

[0020] By satisfying conditional formula (1), the light rays can be incident on the reflecting surface at a high light ray height while being incident and exiting at an angle close to the normal of the reflecting curved surface (generally, the greater the angle of incidence with respect to the surface normal, the greater the aberration of the light rays). This makes it possible to achieve high image quality over a wide focus range. If the upper limit of conditional formula (1) is exceeded, the light rays are largely converged on the front side (object side) of the first transmissive-reflective surface HM1, and the height of the light rays incident on the reflecting surface becomes lower. Therefore, the contribution of the reflecting surface to aberration correction becomes small, making it difficult to achieve high image quality over a wide focus range. On the other hand, if the lower limit of conditional formula (1) is exceeded, the effective diameter of the reflecting surface becomes large, the entire optical system becomes large, and the weight of the lens group (focus group) that is moved during focusing becomes heavy. In addition, the optical system as a whole becomes more of an inverted telephoto type, so the total optical length becomes long. If the weight of the focus group is large, a larger high-thrust motor must be used for autofocusing, which increases the size and manufacturing costs. The refractive power on the object side of the first transmitting-reflecting surface HM1 is, for example, the power of a subgroup from the first surface to the third surface in Numerical Example 1 described later.

[0021] In the optical system of each embodiment, when the axial marginal ray is reflected by the second transmitting-reflecting surface HM2, the distance from the optical axis in a direction perpendicular to the optical axis to the reflection point is defined as Hm2, and the focal length of the optical system (entire system) is defined as f. It is preferable to satisfy the following conditional formula (2):

[0022] 0.15≦Hm2 / f≦3.00 (2) If the upper limit of conditional formula (2) is exceeded, the transmissive-reflective surface becomes too large for the specifications of the optical system, and the entire optical system becomes large. In addition, in the optical systems of the embodiments, the transmissive-reflective surface having reflective power tends to have high tilt sensitivity to aberration. For this reason, it is preferable that the transmissive-reflective surface having reflective power has a tilt adjustment mechanism, and if this mechanism is incorporated, the diameter of the optical system including the lens barrel becomes even larger. On the other hand, if the lower limit of conditional formula (2) is exceeded, the height of the incident light beam on the reflective surface becomes too low, and the axial chromatic aberration cannot be sufficiently corrected. The larger the aperture, the greater the impact of the axial chromatic aberration on the image quality, so it is preferable that the axial chromatic aberration is particularly small in large-diameter lenses such as the optical systems of the embodiments.

[0023] In the optical system of each embodiment, when the distance from the surface closest to the object side to the entrance pupil of the optical system is denoted by dpupil, it is preferable to satisfy the following conditional expression (3):

[0024] 0.0≦dpupil / f≦2.0 (3) Here, the entrance pupil is the entrance pupil for the on-axis light beam (in an optical system with an aperture stop, it is the entrance pupil at full aperture). Exceeding the upper limit of conditional formula (3) is undesirable because it increases the vignetting of the off-axis light beam by the lens barrel and the outer periphery of the lens, resulting in large peripheral light falloff. In order to prevent vignetting, it is necessary to increase the lens diameter on the object side, which leads to an increase in the size of the entire optical system. Note that, by definition, in a typical optical system, the lower limit of conditional formula (3) is not exceeded.

[0025] In the optical system of each embodiment, when the effective diameter of the first transmitting and reflecting surface HM1 is Pm1 and the entrance pupil diameter of the optical system is Ppupil, it is preferable to satisfy the following conditional expression (4).

[0026] 0.6≦Pm1 / Ppupil≦2.0 (4) Here, the entrance pupil is the entrance pupil for the axial light beam. The effective diameter of the first transmission-reflection surface HM1 is the larger of the diameter of the area through which the normal light beam passes and the area through which the normal light beam reflects, in the first transmission-reflection surface HM1. If the upper limit of the conditional formula (4) is exceeded, the effective diameter of the first transmission-reflection surface HM1 is large relative to the entrance pupil diameter, and the weight of the focus group increases. On the other hand, if the lower limit of the conditional formula (4) is not reached, the effective diameter of the first transmission-reflection surface HM1 is small relative to the entrance pupil, and the vignetting of the off-axis light beam increases, leading to large peripheral light falloff. In addition, the first transmission-reflection surface HM1 and the second transmission-reflection surface HM2 cannot sufficiently correct aberrations, and image quality cannot be improved.

[0027] In the optical system of each embodiment, when the F-number of the optical system is Fno, it is preferable to satisfy the following conditional expression (5).

[0028] 0.5≦Fno≦2.5 (5) If the upper limit of conditional expression (5) is exceeded, the amount of light reaching the image plane becomes too small, together with the loss of light amount due to each transmissive reflecting surface, which is not preferable. In addition, a polarizing plate or a polarization selective transmissive reflecting element, which will be described later, generally cannot completely absorb or reflect light in the absorption axis or reflection axis direction, respectively. For this reason, the light of the characteristic error reaches the image plane directly without being reflected by, for example, either of the two semi-transmissive reflecting surfaces, and becomes ghost light. Since the intensity of this ghost light does not depend on the F-number, the relative ghost light intensity is reduced when the F-number is bright. Thus, from the viewpoint of reducing the ghost intensity, it is preferable to be within the range of conditional expression (5). In addition, in the general case where the medium on the image side is air, the lower limit of conditional expression (5) is not exceeded.

[0029] Consider a case where the optical system of each embodiment includes a refractive lens that is disposed closer to the object side than the first transmission-reflection surface HM1 and moves integrally with the first transmission-reflection surface HM1 during focusing, with an air gap between the refractive lens and the first transmission-reflection surface HM1. In this case, when the refractive power on the object side of the lens group that moves integrally with the first transmission-reflection surface HM1 during focusing is φb, it is preferable to satisfy the following conditional expression (6).

[0030] -1.00≦φb / φtotal≦0.70 (6) In focusing, it is generally preferable that the light beam is as close to a parallel light beam as possible incident on the focus group, and by doing so, high image quality can be achieved over a wide focus range. If the upper limit of conditional formula (6) is exceeded, light with a strong convergence tendency is incident on the focus group, which is not preferable for the above reasons. In addition, the back focus will be short unless the focus group has a strong negative power. For this reason, it is not suitable for applications that require a certain degree of back focus, such as lens-interchangeable camera systems. In addition, the light beam is largely converged in front of the first transmissive reflecting surface HM1, and the height of the light beam incident on the reflecting surface is low. Therefore, the contribution of the reflecting surface to aberration correction is small, making it difficult to achieve high image quality over a wide focus range. On the other hand, if the lower limit of conditional formula (6) is exceeded, the effective diameter of the reflecting surface becomes large, the entire optical system becomes large, and the weight of the lens group (focus group) that is moved during focusing becomes heavy. In addition, the optical system as a whole becomes more of an inverted telephoto type, so the total optical length becomes long.

[0031] In the optical system of each embodiment, when the amount of movement (during focusing) when the focal position is changed from infinity to a distance ten times the focal length of the optical system (entire system) is |Δdf|, it is preferable to satisfy the following conditional expression (7).

[0032] 0.005≦|Δdf| / f / Fno≦1.000 ···(7) If the upper limit of conditional expression (7) is exceeded, the amount of movement during focusing becomes too large. The amount of movement of the focus group becomes large, and the optical system becomes large when it is moved. Or, the amount of movement of the focus group becomes too large, and the time required for autofocus becomes long. On the other hand, if the lower limit of conditional expression (7) is exceeded, the amount of focusing becomes too small for the depth of field, making it difficult to finely adjust the focus position.

[0033] In the optical system of each embodiment, it is preferable that the distance (spacing) between the first transmissive-reflective surface HM1 and the second transmissive-reflective surface HM2 changes during focusing. Since normal light passes through the area between the reflective surfaces a total of three times, by making this spacing variable, it is possible to realize high image quality over a wide focus range while suppressing the amount of movement of optical elements accompanying focusing.

[0034] In the optical system of each embodiment, when changing the focal position (when focusing), it is preferable to move the aperture stop SP together with the first transmissive-reflective surface HM1. In this way, the aperture stop SP or the entrance pupil is moved closer to the object side with focusing, so that one-sided aperture can be suppressed when focusing from infinity to close range. One-sided aperture is a phenomenon in which the center of an off-axis light beam passes through a position away from the center of the aperture when the off-axis light beam passes through the aperture. If the distance between the centers is small, this is not a big problem, but if the distance is large, it causes problems such as vignetting when the aperture is narrowed down, or the shape of the blur becomes uneven.

[0035] In the optical system of each embodiment, it is preferable to move the refractive lens arranged outside the region between the first transmission-reflection surface HM1 and the second transmission-reflection surface HM2 with focusing. That is, it is preferable to move at least one of the refractive lenses on the object side of the first transmission-reflection surface HM1 and the refractive lens on the image side of the second transmission-reflection surface HM2 as a focus group (or a floating group). The lens between the two transmission-reflection surfaces acts on the light beam three times, so it has a strong effect on aberration correction, but it is difficult to fine-tune the aberration correction effect. It is also preferable to move the refractive lens located outside the transmission-reflection surface, which acts on the light beam only once and has a gradual effect on aberration, as a focus group (or a floating group).

[0036] In the optical system of each embodiment, it is preferable that the first transmissive reflecting surface HM1 and the second transmissive reflecting surface HM2 do not rotate about the optical axis by 0.5° or more when changing the focusing position. As described later, in the optical system of each embodiment, the relative angles of the 1 / 4 wavelength plate QWP and each transmissive reflecting surface with the optical axis as the rotation axis are important for suppressing ghosts and ensuring the amount of normal light. For this reason, it is preferable that the rotation movement of the first transmissive reflecting surface HM1 and the second transmissive reflecting surface HM2 about the optical axis during focusing is sufficiently small. When all anisotropic elements such as the 1 / 4 wavelength plate QWP and each transmissive reflecting surface rotate by the same amount, there is no problem in terms of suppressing ghosts and ensuring the amount of normal light. However, when the degree of polarization of the light incident on the optical system is not low, the direction of the transmitted polarized light changes due to the equal rotation of each element, which is not preferable because focusing may cause changes in brightness and color depending on the subject.

[0037] In the optical system of each embodiment, when the smaller open angle of the first transmitting / reflecting surface HM1 and the open angle of the second transmitting / reflecting surface HM2 is θm (°), it is preferable to satisfy the following conditional formula (8).

[0038] 0.0≦|θm|≦8.0 (8) Here, the open angle is the angle of the surface normal with respect to the direction perpendicular to the optical axis, and is evaluated as the maximum value within the effective surface. Note that the effective surface is the area through which normal light (i.e., not ghost or stray light) passes.

[0039] As described later, in the optical system of each embodiment, it is preferable that one of the first transmission-reflection surface HM1 or the second transmission-reflection surface HM2 is a polarization selective transmission-reflection element such as a polarizing beam splitter, and the other is a half mirror. The half mirror can be formed by depositing a metal or dielectric multilayer film on glass or resin by vapor deposition or sputtering, so that it can accommodate a relatively wide range of aperture angles. On the other hand, it is difficult to form a polarization selective transmission-reflection element on a curved surface. If the shape is close to a plane, it can be manufactured using a process similar to that of a plane, but the more the shape deviates from a plane, the more special the process becomes. For this reason, if the upper limit of conditional formula (8) is exceeded, it is difficult to form a polarization selective transmission-reflection element. By definition, the lower limit of conditional formula (8) cannot be exceeded.

[0040] In addition, when a flexible material such as a resin film or a wire grid using a resin film as a base material is used as the polarization selective transmission reflection element, it is necessary to maintain the surface accuracy of the transmission reflection surface appropriately. For this reason, when one of the first transmission reflection surface HM1 or the second transmission reflection surface HM2 is made of such a material, it is preferable that it is bonded to glass or a hard resin having a glass transition temperature of 40°C or more. More preferably, it is preferable that both sides are bonded to glass or a hard resin having a glass transition temperature of 40°C or more. Here, the adhesive (including elastic adhesive) used for bonding is not particularly specified, but the adhesive layer is preferably 25 μm or less, and more preferably 15 μm or less. In addition, when only one side is bonded, it is preferable that the holding member does not directly contact the transmission reflection surface when holding the lens. For example, it is preferable to hold it at the bonded glass or hard resin part. In this way, the surface distortion of the transmission reflection surface can be reduced.

[0041] As for surface accuracy, it is preferable to make the roughness of the reflected wavefront sufficiently smooth, and it is preferable that the rms of the components of 1 / mm or more on the reflected wavefront is 10 nm or less, and the rms of the components of 0.05 / mm or more and 1 / mm or less is 10 nm or less. By doing so, it is possible to sufficiently suppress deterioration of image quality due to poor surface accuracy of the reflecting surface.

[0042] In each embodiment, at least one of the first transmissive-reflective surface HM1 or the second transmissive-reflective surface HM2 is preferably a spherical surface. Using an aspherical surface is advantageous for aberration correction, but it is more difficult to make the surface shape closer to the design value than a spherical surface. For this reason, using a spherical surface makes it easier to manufacture. In addition, fine processing marks tend to remain on the aspherical surface, and when such processing marks remain on the reflecting surface in particular, patterns resulting from the processing marks are likely to be reflected in the bokeh. In large-diameter lenses for photography and video applications, users also place importance on the quality of the bokeh, so it is undesirable for such patterns to appear.

[0043] In the optical system of each embodiment, it is preferable to have an anti-vibration group. The anti-vibration group is a group that provides the optical system with a function of preventing blurring such as camera shake by moving an appropriate amount (according to the amount of blurring detected) in a direction perpendicular to the optical axis during shooting. The anti-vibration group is preferably disposed on the object side of the first transmissive reflective surface. In this way, the anti-vibration group can be incorporated without increasing the overall length of the optical system. It is not preferable to use the transmissive reflective surface as the anti-vibration group, since aberrations become large during anti-vibration operation.

[0044] When the optical system of each embodiment has a vibration isolation group, it is preferable to satisfy the following conditional expression (9), where the lateral magnification of the lens group on the image side of the second transmitting and reflecting surface HM2 is β.

[0045] 0.6≦β≦1.5 (9) If the upper limit of conditional expression (9) is exceeded, the number of lens units on the image side of the second transmissive-reflective surface HM2 will increase, increasing the overall length, or the aberration of the lens units on the image side of the second transmissive-reflective surface HM2 will increase. On the other hand, if the lower limit of conditional expression (9) is exceeded, the amount of movement of the vibration isolation group in the direction perpendicular to the optical axis required to obtain a sufficient vibration isolation effect will become too large, making it difficult to configure a drive mechanism that performs vibration isolation.

[0046] The optical system in each embodiment is preferably a coaxial system. This increases the ease of manufacturing each component and facilitates the assembly process. However, the effective diameter and outer diameter of the lenses and the transmitting and reflecting surfaces do not need to be rotationally symmetrical, and for example, rectangular ones may be used.

[0047] The optical system in each embodiment is preferably a primary imaging system. If it is a secondary or higher order imaging system, the light beam that has already been imaged must be re-imaged, and the overall length becomes longer.

[0048] In the optical system of each embodiment, when an autofocus function is provided in a large-diameter lens with an Fno of 1.4 or less, high stopping accuracy of the focus group is required. For this reason, for example, by providing mechanical stoppers at two points, infinity and close range, and moving the focus group so as to press against the stoppers, autofocus can be performed with high stopping accuracy at least for infinity and close range.

[0049] More preferably, the numerical ranges of conditional expressions (1) to (9) are set as shown in the following conditional expressions (1a) to (9a), respectively.

[0050] -0.800≦φfr / φtotal≦0.405 (1a) 0.165≦Hm2 / f≦2.000 (2a) 0.00≦dpupil / f≦1.75 (3a) 0.7≦Pm1 / Ppupil≦1.9 (4a) 0.5≦Fno≦2.4 (5a) -0.75≦φb / φtotal≦0.65 (6a) 0.010≦|Δdf| / f / Fno≦0.900 (7a) 0.0≦|θm|≦6.0 (8a) 0.6≦β≦1.2 (9a) It is even more preferable that the numerical ranges of the conditional expressions (1) to (9) are set as shown in the following conditional expressions (1b) to (9b), respectively.

[0051] -0.5≦φfr / φtotal≦0.35 (1b) 0.18≦Hm2 / f≦1.00 (2b) 0.0≦dpupil / f≦1.4 (3b) 0.75≦Pm1 / Ppupil≦1.85 (4b) 0.52≦Fno≦2.20 (5b) -0.50≦φb / φtotal≦0.60 (6b) 0.015≦|Δdf| / f / Fno≦0.800 (7b) 0.0≦|θm|≦5.0 (8b) 0.6≦β≦1.0 (9b) As described later, in the optical system of each embodiment, it is preferable to use a polarization selective transmission reflection element as either the first transmission reflection surface HM1 or the second transmission reflection surface HM2. Examples of the polarization selective transmission reflection element include "WGF" manufactured by Asahi Kasei Corporation, "IQP-E" manufactured by 3M Company, and "ProFlux" manufactured by Moxtek, Inc. The polarization selective transmission reflection element preferably has a transmittance of about 1% or less on the reflection axis on average in the wavelength range used, more preferably 0.5% or less, and even more preferably 0.25% or less. In this way, stray light that reaches the image plane without being reflected once by the reflection surface (this will be called a "pass-through ghost") can be effectively suppressed. However, even if the polarization selective transmission reflection element has a high transmittance on the reflection axis, the pass-through ghost can be suppressed by using it in combination with a linear polarizer. A half mirror, cholesteric liquid crystal, or the like can be used as the other transmission reflection surface. When a half mirror is used, the amount of randomly polarized light incident from the object side is 12.5% ​​or less by the time it reaches the image plane. By using cholesteric liquid crystal, the amount of light on the image plane can be approximately doubled compared to when a half mirror is used.

[0052] In the optical system of each embodiment, for example, by adopting the following configuration, it is possible to suppress a decrease in the amount of light in the normal imaging optical path while reducing ghost light (unwanted light leakage) from the optical path that transmits without reflecting even once on the transmissive-reflective surface.

[0053] In the optical system of each embodiment, the polarization selective reflecting element may be an optical element created by forming a grid on the lens reflecting surface during molding of the lens and then evaporating, printing or lithographically depositing a metal or dielectric material thereon.

[0054] [Polarized Configuration 1] A configuration using polarized light will be described with reference to FIG. 1. FIG. 1 is a schematic diagram showing the optical path of the optical system in each embodiment. The optical system in each embodiment has two transmission-reflection surfaces. Here, the transmission-reflection surface arranged on the object side of the optical system in each embodiment is configured as a polarization-selective transmission-reflection element (PBS):A. Also, the transmission-reflection surface arranged on the display element side of the optical system in each embodiment is configured as a half mirror (HM):C. Also, a first quarter-wave plate (QWP1):B is arranged between the polarization-selective transmission-reflection element PBS and the half mirror HM. Also, a second quarter-wave plate (QWP2):D and a linear polarizer (POL):E are arranged between the half mirror HM and the imaging surface IM. Here, the polarization-selective transmission-reflection element A is an element configured to reflect linearly polarized light polarized in the same direction as when it is transmitted through the linear polarizer E, and transmit linearly polarized light perpendicular to the reflection.

[0055] The polarization-selective transmission / reflection element is, for example, a wire grid polarizer or a reflective polarizer having a laminated retardation film structure. In this case, the wire grid forming surface or retardation film surface of the polarization-selective transmission / reflection element A functions as a transmission / reflection surface. Note that the wire grid polarizer does not necessarily have to be one in which metal wires are aligned, but it may be one that has thin metal or dielectric layers at a predetermined interval and functions as a polarization-selective transmission / reflection element. For example, an element in which metal or dielectric layers are aligned by vapor deposition can be used.

[0056] The first quarter-wave plate B and the second quarter-wave plate D are arranged with their slow axes inclined at 45° with respect to the polarization transmission axis of the linear polarizer E. Here, it is preferable that the first quarter-wave plate B and the second quarter-wave plate D are arranged with their slow axes inclined at 90°. With this arrangement, when light passes through the first quarter-wave plate B and the second quarter-wave plate D, the wavelength dispersion characteristics of the wave plates are offset. The half mirror C is a half mirror formed by, for example, a dielectric multilayer film or metal deposition, and functions as a transmission and reflection surface. The linear polarizer E is, for example, an absorption-type linear polarizer.

[0057] Next, the optical path selection and operation in the polarization utilization configuration will be explained. Light entering the optical system from the object side becomes linearly polarized light by the polarization-selective transmission / reflection element A, becomes circularly polarized light by the first quarter-wave plate B, and enters the half mirror C. A part of the light that reaches the half mirror C is reflected and becomes circularly polarized light in the reverse direction, returning to the first quarter-wave plate B.

[0058] The counter-circularly polarized light that returned to the first quarter-wave plate B returns to the polarization selective transmission reflector A as linearly polarized light polarized in a direction perpendicular to the direction when the light first passed through the polarization selective transmission reflector A by the first quarter-wave plate B, and is reflected by the polarization selective transmission reflector A. Here, due to the polarization selectivity of the polarization selective transmission reflector A, the linearly polarized light polarized in a direction perpendicular to the direction when the light first passed through the polarization selective transmission reflector A is reflected.

[0059] On the other hand, a portion of the light that reaches the half mirror C is transmitted through the second quarter-wave plate D and becomes linearly polarized light polarized in the same direction as when it passed through the polarization-selective transmission / reflection element A, and is incident on the linear polarizer E and absorbed by the linear polarizer E.

[0060] The light reflected by the polarization-selective transflector A is converted to circularly polarized light by the first quarter-wave plate B and enters the half mirror C. A portion of the light that reaches the half mirror C is transmitted and enters the second quarter-wave plate D. The second quarter-wave plate D causes the incident light to become linearly polarized light that is oriented parallel to the linearly polarized light reflected by the polarization-selective transflector A. The light that passes through the second quarter-wave plate D enters the linear polarizer E. Here, the polarization of the light and the transmission axis of the polarizer coincide, so most of the light is transmitted and directed to the imaging plane IM.

[0061] Due to the above-mentioned action, only the light that has passed through the polarization selective transmission reflector PBS, reflected by the half mirror C, reflected by the polarization selective transmission reflector PBS, and passed through the half mirror C is guided to the imaging plane IM. When a cholesteric liquid crystal is used instead of the half mirror C, it is preferable to set the cholesteric liquid crystal so that it largely reflects the circularly polarized light in the direction of the incident light during the first reflection. In this way, it is possible to increase the amount of light on the normal optical path while reducing ghost light.

[0062] In addition, imaging elements and CCDs (Charge Coupled Devices) that can be used as the imaging surface IM generally have high surface reflectance. In this configuration, the light reflected by the imaging surface IM passes through the linear polarizer E again and is converted into circularly polarized light by the second quarter-wave plate D. After that, the light that leaves the second quarter-wave plate D is reflected by the half mirror C to become circularly polarized light in the opposite direction, and passes through the second quarter-wave plate D again. At this time, the second quarter-wave plate D converts the light into linearly polarized light in a perpendicular direction to the light that was just before passing through the linear polarizer E. Since the direction of this linearly polarized light is perpendicular to the transmission axis of the linear polarizer E, most of the light is absorbed by the linear polarizer E. In this manner, in this configuration, most of the light reflected in sequence from the imaging surface IM, the half mirror C, and the imaging surface IM is cut off, so ghosts and flares related to the imaging surface are less noticeable. In order to obtain such a reflection reduction effect, it is preferable that an optical low-pass filter using birefringence does not exist between the imaging surface and the linear polarizer E. This is because the optical low pass filter causes the polarization state to deviate from the desired polarization state.

[0063] In this configuration, a third quarter-wave plate (not shown) may be disposed immediately after the linear polarizer E. In this case, the angle between the absorption axis of the linear polarizer E and the slow axis of the third quarter-wave plate is preferably 45° or 135° (as viewed from the optical axis direction). This makes it possible to further suppress light reflected at the imaging plane IM and reflections from the lens surface between the third quarter-wave plate and the imaging plane IM.

[0064] In this configuration, a linear polarizer (not shown) may be disposed between the polarization selective transmission reflector A and the object. In this case, the polarization selective transmission reflector A and the linear polarizer are disposed so that their transmission axes coincide with each other. In this way, ghosts that occur when light reflected by the polarization selective transmission reflector A is reflected by a lens surface between the polarization selective transmission reflector A and the object can be reduced. Also, polarized light in the reflection axis direction of the polarization selective transmission reflector A can be largely absorbed, and direct-through ghosts can be greatly reduced. Furthermore, by absorbing ultraviolet rays and the like, the environmental resistance of the polarization selective transmission reflector A can be improved.

[0065] In this configuration, a quarter-wave plate may be placed between the polarization-selective transflector A and the object (if the linear polarizer is placed, it is placed between the linear polarizer and the object). In this case, the quarter-wave plate is placed so that the fast axis or slow axis of the quarter-wave plate forms an angle of 45° with the transmission axis of the polarization-selective transflector A. In this way, pseudo depolarization is performed, and even if the light incident from the object side is linearly polarized, it is possible to capture an image regardless of its polarization direction. A depolarizing element may be placed instead of the quarter-wave plate. For example, the product name "Cosmoshine SRF" by Toyobo Co., Ltd. can be used as the depolarizing element. Cosmoshine SRF is a film with a large birefringence of around 10,000 nm, and by using such a film, it may be possible to prevent color unevenness caused by the wavelength characteristics and angle characteristics of the wave plate compared to the case of using a quarter-wave plate.

[0066] [Polarized Configuration 2] Next, a configuration using polarized light will be described with reference to FIG. 2. FIG. 2 is a schematic diagram showing the optical path of the optical system in each embodiment. The optical system in each embodiment has two transmission-reflection surfaces. Here, the transmission-reflection surface arranged on the object side of the optical system in each embodiment is configured as a half mirror (HM):C. Also, the transmission-reflection surface arranged on the display element side of the optical system in each embodiment is configured as a polarization-selective transmission-reflection element (PBS):A. Also, a first quarter-wave plate (QWP1):B is arranged between the polarization-selective transmission-reflection element PBS and the half mirror HM. Also, a linear polarizer (POL):E and a second quarter-wave plate (QWP2):D are arranged between the half mirror HM and the object surface. Here, the configuration of each polarizing element and the suitable arrangement of the optical axis orientation are the same as those of the configuration 1 using polarized light.

[0067] Next, the optical path selection and operation in the polarization utilization configuration will be explained. Light entering the optical system from the object side becomes linearly polarized light by linear polarizer E, becomes circularly polarized light by second quarter-wave plate E, and enters half mirror C. Part of the light that reaches half mirror C is reflected and becomes circularly polarized light in the reverse direction, returning to second quarter-wave plate D.

[0068] The light that reaches and is reflected by the half mirror C is circularly polarized in the opposite direction to when it was incident. This light is then transformed by the second quarter-wave plate D into linearly polarized light that is polarized in a direction perpendicular to when it passed through the linear polarizer E, and is then incident on and absorbed by the linear polarizer E.

[0069] On the other hand, the light transmitted through the half mirror C is converted by the first quarter-wave plate B into linearly polarized light polarized in the same direction as the light immediately after transmitting through the linear polarizer E. This linearly polarized light is reflected by the polarization-selective transmission / reflection element A and returns to the first quarter-wave plate B. The light is then converted into circularly polarized light by the first quarter-wave plate B, and a portion of it is reflected by the half mirror C. The light reflected by the half mirror C enters the first quarter-wave plate B again and is converted into linearly polarized light whose polarization direction is orthogonal to that when the light was reflected by the polarization-selective transmission / reflection element A. This linearly polarized light passes through the polarization-selective transmission / reflection element A and is guided to the imaging plane IM.

[0070] By the above action, only the light that is transmitted through the half mirror C, reflected by the polarization selective transmission / reflection element PBS, reflected by the half mirror C, and transmitted through the polarization selective transmission / reflection element PBS is guided to the imaging plane IM.

[0071] In this arrangement, a linear polarizer A' may be placed between the polarization-selective transflector A and the imaging plane IM. In this case, the transmission axes of the linear polarizer A' and the polarization-selective transflector A are aligned. In this way, it is possible to absorb light that is reflected by the imaging plane IM, then reflected by the polarization-selective transflector A, and then again enters the imaging plane IM to cause ghosts and flare. In addition, it is possible to largely absorb light that leaks from the reflection axis direction of the polarization-selective transflector A, greatly reducing direct-through ghosts.

[0072] In this configuration, a quarter-wave plate may be disposed between the linear polarizer E and the object. In this case, the quarter-wave plate is disposed so that the fast axis or slow axis of the quarter-wave plate forms an angle of 45° with the transmission axis of the linear polarizer E. In this way, even if the light incident from the object side is linearly polarized, it is possible to capture an image regardless of its polarization direction. Also, a depolarizing element may be disposed instead of the quarter-wave plate. For example, "Cosmoshine SRF" by Toyobo Co., Ltd. can be used as the depolarizing element.

[0073] In the above explanation of the two configurations, terms such as orthogonal, parallel, and 45° are used, but these do not necessarily have to be strictly 90°, 0°, and 45°. However, they should be within ±5° of the desired angle, preferably within ±2°, and more preferably within ±1°.

[0074] In both of the above two configurations, it is desirable to use the same two quarter-wave plates QWP. There is no problem if the quarter-wave plates QWP are ideal (i.e., they give a phase of exactly 1 / 4 wavelength to all wavelengths and all light incidence angles within the range of use). However, in reality, such quarter-wave plates QWP do not exist, and the phase given to light differs depending on the wavelength of the transmitted light. In the above two configurations, when light passes through the two quarter-wave plates QWP, the phases given by the first quarter-wave plate QWP1 and the second quarter-wave plate QWP2 are offset, so that only the desired light is emitted to the image surface. In other words, the light that has been reflected once by the first and second transmissive-reflective surfaces is emitted to the image surface, and the light that has not been reflected once is absorbed by the polarizing plate. In this case, if the characteristics of the first quarter-wave plate QWP1 and the second quarter-wave plate QWP2 differ from each other, unintended light will be emitted toward the image plane accordingly, causing ghosts and flares and degrading image quality.

[0075] In the above two types of configurations, it is preferable that the linear polarizer E is an absorption type polarizer rather than a reflection type polarizer. This is because the absorption type polarizer is less likely to cause ghosts and flares due to reflection. For the linear polarizer E, the transmittance of the absorption axis is preferably about 0.5% or less, more preferably 0.15% or less, and even more preferably 0.05% or less, on average in the wavelength range used. In this way, ghost light that reaches the image plane without being reflected once on the reflection surface can be effectively suppressed. In particular, when the wavelength range used is wide, it is difficult to keep the transmittance of the absorption axis of the polarizer low, but multiple polarizers may be used in layers to obtain the desired characteristics. As the linear polarizer E, for example, the product names "ACE-125U" and "VHC-12UL2S" manufactured by Nippon Kayaku Co., Ltd., or the product name "XP42HE" manufactured by Edmund Optics Japan Co., Ltd. can be used in the visible range. In addition, for example, by stacking "ACE-125U" and "SHC-115U" manufactured by Nippon Kayaku Co., Ltd., it is possible to create a linear polarizing plate with extremely low transmittance on the absorption axis. By stacking multiple polarizing plates in this way, it is possible to increase resistance to deterioration over time.

[0076] In addition, the above two types of configurations are considered in combination with an imaging element including an optical low-pass filter. In this case, it is preferable that the relative angle between the transmission axis of the polarizing plate closest to the image side and the fast axis of the birefringent plate closest to the object side among the birefringent plates constituting the optical low-pass filter is 45° or 135°. In this way, a low-pass effect similar to that of a normal optical system (not dependent on polarization like a general refractive optical system) can be obtained. Alternatively, a quarter-wave plate may be further arranged on the image side of the polarizing plate closest to the image side. In this case, it is preferable that the transmission axis of the polarizing plate closest to the image side and the fast axis of the quarter-wave plate are 45° or 135°. In this way, a circularly polarized light is emitted toward the imaging element, thereby obtaining a low-pass effect similar to that of a normal optical system. Alternatively, a plastic molded lens with large birefringence may be arranged on the image side of the polarizing plate closest to the image side to make the emitted light pseudo-randomly polarized, thereby obtaining a low-pass effect similar to that of a normal optical system.

[0077] In the above two types of configurations, the polarization selective transmission reflection element, the quarter wave plate, and the linear polarizer may be circular, rectangular, or polygonal. If the shape is such that they can be laid out on a plane without any margin, such as a rectangle or a regular hexagon, each element can be used without waste, which is preferable in terms of manufacturing costs. Among these optical elements, those made mainly of polymer materials are available at low cost. When using such elements, it is preferable to bond them to glass or resin, for example, as described above, to ensure sufficient surface accuracy. In such a form, it is possible to eliminate material loss by bonding them in a large size and cutting out the necessary amount for the rectangle from there. In addition, as described above, the azimuth between each element is important in the above two types of configurations. By using rectangular elements, it becomes easier to guarantee the outer shape of the parts and the orientation of the elements (fast axis / slow axis, transmission axis / absorption axis, transmission axis / reflection axis) for each part, and the adjustment of the azimuth can be simplified or omitted.

[0078] In the optical system of each embodiment, the lens may be made of a resin material or a glass material. However, it is preferable that the lens disposed between the first and second transmission-reflection surfaces has low birefringence.

[0079] The optical system of each embodiment has a first refractive lens L1, a first transmission-reflection surface HM1, a quarter-wave plate QWP, and a second transmission-reflection surface HM2 arranged in this order from the object side to the image side. During focusing, the first transmission-reflection surface HM1 moves in the optical axis direction. During focusing, the first refractive lens L1 does not move, or the distance between the first transmission-reflection surface HM1 and the first transmission-reflection surface HM1 in the optical axis direction changes. The first refractive lens L1 is separated from both the first transmission-reflection surface HM1 and the second transmission-reflection surface HM2.

[0080] Alternatively, the optical system of each embodiment has a first refractive lens L1, a first transmission-reflection surface HM1, a quarter-wave plate QWP, a second transmission-reflection surface HM2, and a second refractive lens L2, arranged in this order from the object side to the image side. During focusing, the first transmission-reflection surface moves in the optical axis direction. During focusing, the second refractive lens L2 does not move or the distance between the second refractive lens L2 and the first transmission-reflection surface HM1 in the optical axis direction changes. The second refractive lens L2 is separated from both the first transmission-reflection surface HM1 and the second transmission-reflection surface HM2.

[0081] The optical system of each embodiment may have a third refractive lens that is disposed closer to the object side than the first transmission-reflection surface HM1, is separated from the first transmission-reflection surface HM1, and moves integrally with the first transmission-reflection surface HM1 during focusing. The optical system of each embodiment may also have a fourth refractive lens that is disposed outside the region between the first transmission-reflection surface HM1 and the second transmission-reflection surface HM2, and moves in the optical axis direction during focusing.

[0082] The optical system of each embodiment will be described in detail below. EXAMPLES

[0083] First, the optical system OS1 in the first embodiment will be described with reference to Fig. 3 and Fig. 4. Fig. 3 is a cross-sectional view of the optical system OS1. The optical system OS1 is configured to include a plurality of lenses (a plurality of lens groups) and a sensor protection glass arranged in order from the object side to the image surface IM side. In addition, a quarter-wave plate QWP is arranged on the image side of the first transmissive-reflective surface HM1.

[0084] FIG. 4(a) is an aberration diagram of the optical system OS1 when focused at infinity, and FIG. 4(b) is an aberration diagram of the optical system OS1 when focused at a close distance. In the spherical aberration diagram, Fno is the F-number, and the amount of spherical aberration for the d-line (wavelength 587.6 nm), g-line (wavelength 435.8 nm), C-line (wavelength 656.3 nm), and F-line (wavelength 486.1 nm) is shown. In the astigmatism diagram, S is the amount of astigmatism in the sagittal image plane, and M is the amount of astigmatism in the meridional image plane. In the distortion aberration diagram, the amount of distortion for the d-line is shown. In the chromatic aberration diagram, the amount of chromatic aberration for the g-line, C-line, and F-line is shown. ω is the half angle of view (°). obj is the focused position (the distance from the imaging plane IM to the focal plane) (unit: mm). These are the same in the subsequent aberration diagrams.

[0085] During focusing, the optical system OS1 moves the lens group including the first transmissive-reflective surface HM1 and the aperture stop SP together in the optical axis direction. In Fig. 1, the lens group to be moved and the direction of movement when focusing from infinity to a close distance are indicated by arrows at the bottom. In Fig. 3, the arrow points toward the object side, indicating that the lens is moved toward the object side when focusing from infinity to a close distance. This is the same in the subsequent optical path diagrams.

[0086] In the optical system OS1, the lens closest to the object side corresponds to the first refractive lens L1. EXAMPLES

[0087] Next, the optical system OS2 in Example 2 will be described with reference to Fig. 5 and Fig. 6. Fig. 5 is a cross-sectional view of the optical system OS2. Fig. 6(a) is an aberration diagram of the optical system OS2 when focused at infinity, and Fig. 6(b) is an aberration diagram of the optical system OS2 when focused at a close distance.

[0088] The optical system OS2 is configured to include a plurality of lenses (a plurality of lens groups) and a sensor protection glass arranged in order from the object side to the image surface IM side. In addition, a quarter-wave plate QWP is arranged on the image side of the first transmissive-reflective surface HM1, sandwiching a sheet of flat glass. With this configuration, the surface accuracy of the reflective surface can be easily improved. In this embodiment, the quarter-wave plate QWP is incorporated into the optical path diagram and numerical values ​​as a flat plate with a thickness of 0.1 mm, but this has almost no effect on the aberration, and the presence or absence of this thickness does not affect the essence of each embodiment, so the thickness of the quarter-wave plate QWP is omitted in Example 1. Hereafter, the thickness of the quarter-wave plate QWP, the transmissive-reflective surface, etc. may be omitted. During focusing, the optical system OS2 moves the lens group (including the aperture stop SP) on the object side of the meniscus lens with the convex surface facing the object side as a whole in the optical axis direction.

[0089] In the optical system OS2, for example, the lens closest to the object side corresponds to the first refractive lens L1, the third refractive lens, and the fourth refractive lens, and the lens closest to the image side corresponds to the second refractive lens L2. EXAMPLES

[0090] Next, an optical system OS3 in Example 3 will be described with reference to Fig. 7 and Fig. 8. Fig. 7 is a cross-sectional view of the optical system OS3. Fig. 8(a) is an aberration diagram of the optical system OS3 when focused at infinity, and Fig. 8(b) is an aberration diagram of the optical system OS3 when focused at a close distance.

[0091] The optical system OS3 is configured to include a plurality of lenses (a plurality of lens groups) and a sensor protection glass arranged in order from the object side to the image surface IM side. In addition, a quarter-wave plate QWP is arranged on the image side of the first transmitting and reflecting surface HM1 with a convex lens sandwiched therebetween. During focusing, the optical system OS3 moves the seven lens groups (counting the flat plate but not the quarter-wave plate QWP) from the object side and the aperture stop SP as a single unit in the optical axis direction.

[0092] In the optical system OS3, for example, the lens closest to the object corresponds to the first refractive lens L1, the third refractive lens, and the fourth refractive lens, and the lens closest to the image corresponds to the second refractive lens L2. EXAMPLES

[0093] Next, the optical system OS4 in Example 4 will be described with reference to Fig. 9 and Fig. 10. Fig. 9 is a cross-sectional view of the optical system OS4. Fig. 10(a) is an aberration diagram of the optical system OS4 when focused at infinity, and Fig. 10(b) is an aberration diagram of the optical system OS4 when focused at a close distance.

[0094] The optical system OS4 is configured to include a plurality of lenses (a plurality of lens groups) and a sensor protection glass arranged in order from the object side to the image surface IM side. In addition, a quarter-wave plate QWP is arranged on the image side of the first transmitting and reflecting surface HM1. During focusing, the optical system OS4 moves the seven lens groups on the image side immediately behind the aperture stop SP as a whole in the optical axis direction. In addition, image stabilization can be performed by moving the fourth and fifth cemented lenses (anti-vibration groups) from the object side in a direction perpendicular to the optical axis.

[0095] In the optical system OS4, for example, the lens closest to the object corresponds to the first refractive lens L1, the lenses immediately behind the aperture stop SP correspond to the third and fourth refractive lenses, and the lens closest to the image corresponds to the second refractive lens L2. EXAMPLES

[0096] Next, an optical system OS5 in Example 5 will be described with reference to Fig. 11 and Fig. 12. Fig. 11 is a cross-sectional view of the optical system OS5. Fig. 12(a) is an aberration diagram of the optical system OS5 when focused at infinity, and Fig. 12(b) is an aberration diagram of the optical system OS5 when focused at a close distance.

[0097] The optical system OS5 is configured to include a plurality of lenses (a plurality of lens groups) and a sensor protection glass arranged in order from the object side to the image surface IM side. Also, a quarter-wave plate QWP is arranged on the image side of the first transmitting and reflecting surface HM1. During focusing, the optical system OS5 moves the three lens groups on the image side immediately after the aperture stop SP as a unit in the optical axis direction.

[0098] In the optical system OS5, for example, the lens closest to the object corresponds to the first refractive lens L1, the lenses immediately behind the aperture stop SP correspond to the third and fourth refractive lenses, and the lens closest to the image corresponds to the second refractive lens L2. EXAMPLES

[0099] Next, an optical system OS6 in Example 6 will be described with reference to Fig. 13 and Fig. 14. Fig. 13 is a cross-sectional view of the optical system OS6. Fig. 14(a) is an aberration diagram of the optical system OS6 when focused at infinity, and Fig. 14(b) is an aberration diagram of the optical system OS6 when focused at a close distance.

[0100] The optical system OS6 is configured to include a plurality of lenses (a plurality of lens groups) and a sensor protection glass arranged in order from the object side to the image surface IM side. Also, a quarter-wave plate QWP is arranged on the image side of the first transmitting and reflecting surface HM1. During focusing, the optical system OS6 moves the aperture stop SP and the two lenses on the image side immediately behind the aperture stop SP as a single unit in the optical axis direction. In the optical system OS6, for example, the lens closest to the object side corresponds to the first refractive lens L1, and the lens closest to the image side corresponds to the second refractive lens L2. EXAMPLES

[0101] Next, an optical system OS7 in Example 7 will be described with reference to Fig. 15 and Fig. 16. Fig. 15 is a cross-sectional view of the optical system OS7. Fig. 16(a) is an aberration diagram of the optical system OS7 when focused at infinity, and Fig. 16(b) is an aberration diagram of the optical system OS7 when focused at a close distance.

[0102] The optical system OS7 is configured to include a plurality of lenses (a plurality of lens groups) and a sensor protection glass arranged in order from the object side to the image surface IM side. In addition, a quarter-wave plate QWP is arranged on the image side of the first transflective surface HM1. During focusing, the optical system OS7 moves the aperture stop SP, one lens 1 on the object side immediately before the aperture stop SP, and five lenses (counting the flat plate) on the image side immediately after the aperture stop SP as a single unit in the optical axis direction. In addition, image stabilization can be performed by moving the lens (anti-vibration group) on the image side immediately after the aperture stop SP in a direction perpendicular to the optical axis.

[0103] In the optical system OS7, for example, the lens closest to the object corresponds to the first refractive lens L1, the lenses immediately before the aperture stop SP correspond to the third and fourth refractive lenses, and the lens closest to the image corresponds to the second refractive lens L2. EXAMPLES

[0104] Next, an optical system OS8 in Example 8 will be described with reference to Fig. 17 and Fig. 18. Fig. 18(a) is an aberration diagram of the optical system OS8 when focused on infinity, and Fig. 18(b) is an aberration diagram of the optical system OS8 when focused on a close distance.

[0105] The optical system OS8 is configured with a plurality of lenses (a plurality of lens groups) and a sensor protection glass arranged in order from the object side to the image surface IM side. During focusing, the optical system OS8 moves the four lenses (counting the flat plate, not counting the quarter-wave plate) on the image side immediately behind the aperture stop SP as a whole in the optical axis direction. In addition, image stabilization can be performed by moving the cemented lens (anti-vibration group) on the object side immediately before the aperture stop SP in a direction perpendicular to the optical axis. In the optical system OS8, for example, the lens closest to the object corresponds to the first refractive lens L1, the lens immediately behind the second transmissive reflective surface HM2 corresponds to the fourth refractive lens, and the lens closest to the image corresponds to the second refractive lens L2. EXAMPLES

[0106] Next, an optical system OS9 in Example 9 will be described with reference to Fig. 19 and Fig. 20. Fig. 19 is a cross-sectional view of the optical system OS9. Fig. 20(a) is an aberration diagram of the optical system OS9 when focused on infinity, and Fig. 20(b) is an aberration diagram of the optical system OS9 when focused on a close distance.

[0107] The optical system OS9 is configured with a plurality of lenses (a plurality of lens groups) and a sensor protection glass arranged in order from the object side to the image surface IM side. During focusing, the optical system OS9 moves the aperture stop SP and the two lenses on the image side immediately behind the aperture stop SP as a single unit in the optical axis direction.

[0108] In the optical system OS9, for example, the lens closest to the object corresponds to the first refractive lens L1, and the lenses immediately behind the aperture stop SP correspond to the third refractive lens and the fourth refractive lens. EXAMPLES

[0109] Next, an optical system OS10 in Example 10 will be described with reference to Fig. 21 and Fig. 22. Fig. 21 is a cross-sectional view of the optical system OS10. Fig. 22(a) is an aberration diagram of the optical system OS10 when focused at infinity, and Fig. 22(b) is an aberration diagram of the optical system OS10 when focused at a close distance.

[0110] The optical system OS10 is configured to include a plurality of lenses (a plurality of lens groups) and a sensor protection glass arranged in order from the object side to the image surface IM side. During focusing, the optical system OS10 moves the aperture stop SP and the lenses immediately before and immediately after the aperture stop SP as a unit in the optical axis direction, and also moves the two lenses on the image side as a unitary floating group by a different amount in the optical axis direction.

[0111] In the optical system OS10, for example, the lens closest to the object corresponds to the first refractive lens, the third refractive lens, and the fourth refractive lens, and the lens closest to the image corresponds to the second refractive lens L2. EXAMPLES

[0112] Next, an optical system OS11 in Example 11 will be described with reference to Fig. 23 and Fig. 24. Fig. 23 is a cross-sectional view of the optical system OS11. Fig. 24(a) is an aberration diagram of the optical system OS11 when focused at infinity, and Fig. 24(b) is an aberration diagram of the optical system OS11 when focused at a close distance.

[0113] The optical system OS11 is configured to include a plurality of lenses (a plurality of lens groups) and a sensor protection glass arranged in order from the object side to the image surface IM side. During focusing, the optical system OS11 moves the aperture stop SP and the two lenses on the image side immediately behind the aperture stop SP as a single unit in the optical axis direction.

[0114] In the optical system OS11, for example, the lens closest to the object corresponds to the first refractive lens L1, and the lens immediately behind the aperture stop SP corresponds to the fourth refractive lens. EXAMPLES

[0115] Next, the optical system OS12 in Example 12 will be described with reference to Fig. 25 and Fig. 26. Fig. 25 is a cross-sectional view of the optical system OS12. Fig. 26(a) is an aberration diagram of the optical system OS12 when focused on infinity, and Fig. 26(b) is an aberration diagram of the optical system OS12 when focused on a close distance.

[0116] The optical system OS12 is configured to include a plurality of lenses (a plurality of lens groups) and a sensor protection glass arranged in order from the object side to the image surface IM side. During focusing, the optical system OS12 moves the aperture stop SP and the three lenses on the image side immediately behind the aperture stop SP as a single unit in the optical axis direction.

[0117] In the optical system OS12, for example, the lens closest to the object corresponds to the first refractive lens L1, and the lenses immediately behind the aperture stop SP correspond to the third refractive lens and the fourth refractive lens. EXAMPLES

[0118] Next, the optical system OS13 in Example 13 will be described with reference to Fig. 27 and Fig. 28. Fig. 27 is a cross-sectional view of the optical system OS13. Fig. 28(a) is an aberration diagram of the optical system OS13 when focused at infinity, and Fig. 28(b) is an aberration diagram of the optical system OS13 when focused at a close distance.

[0119] The optical system OS13 is configured to include a plurality of lenses (a plurality of lens groups) and a sensor protection glass arranged in order from the object side to the image surface IM side. During focusing, the optical system OS13 does not move a total of three lenses, namely, the two lenses closest to the object side and the one lens closest to the image side, but moves the remaining lens groups and the aperture stop SP together in the optical axis direction. In the optical system OS13, for example, the lens closest to the object corresponds to the first refractive lens L1, and the lenses immediately before the aperture stop SP correspond to the third refractive lens and the fourth refractive lens. EXAMPLES

[0120] Next, the optical system OS14 in Example 14 will be described with reference to Fig. 29 and Fig. 30. Fig. 29 is a cross-sectional view of the optical system OS14. Fig. 30(a) is an aberration diagram of the optical system OS14 when focused at infinity, and Fig. 30(b) is an aberration diagram of the optical system OS14 when focused at a close distance.

[0121] The optical system OS14 is configured to include a plurality of lenses (a plurality of lens groups) and a sensor protection glass arranged in order from the object side to the image surface IM side. During focusing, the optical system OS14 moves the aperture stop SP and the two lenses on the image side immediately behind the aperture stop SP as a single unit in the optical axis direction.

[0122] In the optical system OS14, for example, the lens closest to the object corresponds to the first refractive lens L1, and the lens immediately after the aperture stop corresponds to the fourth refractive lens. EXAMPLES

[0123] Next, an optical system OS15 in Example 15 will be described with reference to Fig. 31 and Fig. 32. Fig. 31 is a cross-sectional view of the optical system OS15. Fig. 32(a) is an aberration diagram of the optical system OS15 when focused at infinity, and Fig. 32(b) is an aberration diagram of the optical system OS15 when focused at a close distance.

[0124] The optical system OS15 is configured to include a plurality of lenses (a plurality of lens groups) and a sensor protection glass arranged in order from the object side to the image surface IM side. During focusing, the optical system OS15 moves the aperture stop SP and the two lenses on the image side immediately behind the aperture stop SP as a single unit in the optical axis direction.

[0125] In the optical system OS15, for example, the lens closest to the object corresponds to the first refractive lens L1, and the lens immediately behind the aperture stop SP corresponds to the fourth refractive lens. EXAMPLES

[0126] Next, the optical system OS16 in Example 16 will be described with reference to Fig. 33 and Fig. 34. Fig. 33 is a cross-sectional view of the optical system OS16. Fig. 34(a) is an aberration diagram of the optical system OS16 when focused on infinity, and Fig. 34(b) is an aberration diagram of the optical system OS16 when focused on a close distance.

[0127] The optical system OS16 is configured with a plurality of lenses (a plurality of lens groups) and a sensor protection glass arranged in order from the object side to the image surface IM side. During focusing, the optical system OS16 moves the aperture stop SP and the three lenses on the image side immediately behind the aperture stop SP as a single unit in the optical axis direction.

[0128] In the optical system OS16, for example, the lens closest to the object corresponds to the first refractive lens, and the lens immediately behind the aperture stop SP corresponds to the fourth refractive lens. EXAMPLES

[0129] Next, the optical system OS17 in Example 17 will be described with reference to Fig. 35 and Fig. 36. Fig. 35 is a cross-sectional view of the optical system OS17. Fig. 36(a) is an aberration diagram of the optical system OS17 when focused at infinity, and Fig. 36(b) is an aberration diagram of the optical system OS17 when focused at a close distance.

[0130] The optical system OS17 is configured to include a plurality of lenses (a plurality of lens groups) and a sensor protection glass arranged in order from the object side to the image surface IM side. During focusing, the optical system OS17 moves the three lenses on the image side immediately behind the aperture stop SP as a single unit in the optical axis direction.

[0131] In the optical system OS17, the power of the optical system acting on the through light that reaches the image plane without being reflected by either the first transmissive-reflective surface HM1 or the second transmissive-reflective surface HM2 is strengthened. In reality, it is undesirable for the through light to reach the image plane, and it is preferable for it to be absorbed by a polarizing plate, but due to factors such as the non-ideal characteristics of the polarizing plate, it is unavoidable that some through light reaches the image plane. This configuration makes it possible to prevent ghosts caused by through light from spreading across the entire screen.

[0132] In the optical system OS17, for example, the lens closest to the object corresponds to the first refractive lens L1, and the lenses immediately behind the aperture stop SP correspond to the third refractive lens and the fourth refractive lens. EXAMPLES

[0133] Next, the optical system OS18 in Example 18 will be described with reference to Fig. 37 and Fig. 38. Fig. 37 is a cross-sectional view of the optical system OS18. Fig. 38(a) is an aberration diagram of the optical system OS18 when focused at infinity, and Fig. 38(b) is an aberration diagram of the optical system OS18 when focused at a close distance.

[0134] The optical system OS18 is configured to include a plurality of lenses (a plurality of lens groups) and a sensor protection glass arranged in order from the object side to the image surface IM side. During focusing, the optical system OS18 does not move a total of two lenses, the lens closest to the object side and the lens closest to the image side, but moves the remaining lens groups and the aperture stop SP together in the optical axis direction.

[0135] In the optical system OS18, for example, the lens closest to the object corresponds to the first refractive lens L1, and the lenses immediately before the aperture stop SP correspond to the third refractive lens and the fourth refractive lens. EXAMPLES

[0136] Next, an optical system OS19 in Example 19 will be described with reference to Fig. 39 and Fig. 40. Fig. 39 is a cross-sectional view of the optical system OS19. Fig. 40(a) is an aberration diagram of the optical system OS19 when focused at infinity, and Fig. 40(b) is an aberration diagram of the optical system OS19 when focused at a close distance.

[0137] The optical system OS19 is configured to include a plurality of lenses (a plurality of lens groups) and a sensor protection glass arranged in order from the object side to the image surface IM side. During focusing, the optical system OS19 moves the aperture stop SP and the image side lens immediately behind the aperture stop SP as a unit in the optical axis direction, and also moves the two lenses closest to the image side by a different amount in the optical axis direction as a unitary floating group.

[0138] In the optical system OS19, for example, the lens closest to the object corresponds to the first refractive lens L1, and the lens immediately behind the aperture stop SP corresponds to the fourth refractive lens. EXAMPLES

[0139] Next, an optical system OS20 in Example 20 will be described with reference to Fig. 41 and Fig. 42. Fig. 41 is a cross-sectional view of the optical system OS20. Fig. 42(a) is an aberration diagram of the optical system OS20 when focused at infinity, and Fig. 42(b) is an aberration diagram of the optical system OS20 when focused at a close distance.

[0140] The optical system OS20 is configured to include a plurality of lenses (a plurality of lens groups) and a sensor protection glass arranged in order from the object side to the image surface IM side. During focusing, the optical system OS20 moves the aperture stop SP and the two lenses on the image side immediately behind the aperture stop SP as a single unit in the optical axis direction.

[0141] In the optical system OS20, for example, the lens closest to the object corresponds to the first refractive lens L1, and the lens immediately behind the aperture stop SP corresponds to the fourth refractive lens. EXAMPLES

[0142] Next, the optical system OS21 in Example 21 will be described with reference to Fig. 43 and Fig. 44. Fig. 43 is a cross-sectional view of the optical system OS21. Fig. 44(a) is an aberration diagram of the optical system OS21 when focused at infinity, and Fig. 44(b) is an aberration diagram of the optical system OS21 when focused at a close distance.

[0143] The optical system OS21 is configured to include a plurality of lenses (a plurality of lens groups) and a sensor protection glass, which are arranged in order from the object side to the image surface IM side. During focusing, the optical system OS21 moves one lens on the image side immediately behind the aperture stop SP in the optical axis direction.

[0144] In the optical system OS21, for example, the lens closest to the object side corresponds to the first refractive lens L1. EXAMPLES

[0145] Next, the optical system OS22 in Example 22 will be described with reference to Fig. 45 and Fig. 46. Fig. 45 is a cross-sectional view of the optical system OS22. Fig. 46(a) is an aberration diagram of the optical system OS22 when focused at infinity, and Fig. 46(b) is an aberration diagram of the optical system OS22 when focused at a close distance.

[0146] The optical system OS22 is configured to include a plurality of lenses (a plurality of lens groups) and a sensor protection glass arranged in order from the object side to the image surface IM side. During focusing, the optical system OS22 moves two cemented lenses, the fifth and sixth lenses from the object side, in the optical axis direction.

[0147] In the optical system OS22, for example, the lens closest to the object corresponds to the first refractive lens L1, and the lens immediately behind the aperture stop SP corresponds to the fourth refractive lens. EXAMPLES

[0148] Next, the optical system OS23 in Example 23 will be described with reference to Fig. 47 and Fig. 48. Fig. 47 is a cross-sectional view of the optical system OS23. Fig. 48(a) is an aberration diagram of the optical system OS23 when focused at infinity, and Fig. 48(b) is an aberration diagram of the optical system OS23 when focused at a close distance.

[0149] The optical system OS23 is configured to include a plurality of lenses (a plurality of lens groups) and a sensor protection glass arranged in order from the object side to the image surface IM side. During focusing, the optical system OS23 moves the lens groups other than the lens closest to the image side and the aperture stop SP together in the optical axis direction.

[0150] In the optical system OS23, for example, the lens closest to the object corresponds to the first refractive lens L1, the third refractive lens, and the fourth refractive lens, and the lens closest to the image corresponds to the second refractive lens L2. EXAMPLES

[0151] Next, the optical system OS24 in Example 24 will be described with reference to Fig. 49 and Fig. 50. Fig. 49 is a cross-sectional view of the optical system OS24. Fig. 50(a) is an aberration diagram of the optical system OS24 when focused at infinity, and Fig. 50(b) is an aberration diagram of the optical system OS24 when focused at a close distance.

[0152] The optical system OS24 is configured with a plurality of lenses (a plurality of lens groups) and a sensor protection glass arranged in order from the object side to the image surface IM side. During focusing, the optical system OS24 moves the sixth lens counting from the object side in the optical axis direction.

[0153] In the optical system OS24, for example, the lens closest to the object corresponds to the first refractive lens L1, and the lens having the first transmissive / reflective surface HM1 corresponds to the fourth refractive lens. EXAMPLES

[0154] Next, an optical system OS25 in Example 25 will be described with reference to Fig. 51 and Fig. 52. Fig. 51 is a cross-sectional view of the optical system OS25. Fig. 52(a) is an aberration diagram of the optical system OS25 when focused at infinity, and Fig. 52(b) is an aberration diagram of the optical system OS25 when focused at a close distance.

[0155] The optical system OS25 is configured to include a plurality of lenses (a plurality of lens groups) and a sensor protection glass, which are arranged in order from the object side to the image surface IM side. During focusing, the optical system OS25 moves a flat plate on the image side immediately behind the aperture stop SP in the optical axis direction.

[0156] In the optical system OS25, for example, the lens closest to the object side corresponds to the first refractive lens L1. EXAMPLES

[0157] Next, the optical system OS26 in Example 26 will be described with reference to Fig. 53 and Fig. 54. Fig. 53 is a cross-sectional view of the optical system OS26. Fig. 54(a) is an aberration diagram of the optical system OS26 when focused at infinity, and Fig. 54(b) is an aberration diagram of the optical system OS26 when focused at a close distance.

[0158] The optical system OS26 is configured to include a plurality of lenses (a plurality of lens groups) and a sensor protection glass arranged in order from the object side to the image surface IM side. During focusing, the optical system OS26 moves the three lenses other than the lens closest to the object side and the aperture stop SP as a single unit.

[0159] In the optical system OS26, for example, the lens closest to the object corresponds to the first refractive lens L1, and the lens immediately behind the aperture stop SP corresponds to the fourth refractive lens.

[0160] Numerical Examples 1 to 26 corresponding to Examples 1 to 23 are shown below. In the surface data of each numerical example, surface number i indicates the i-th surface when counted from the pupil surface side. r is the radius of curvature of the i-th surface (mm), d is the lens thickness or air gap (mm) between the i-th and (i+1)-th surfaces, and nd is the refractive index of the material of the i-th optical component at the d-line. νd is the Abbe number based on the d-line of the material of the i-th optical component. The Abbe number νd is expressed as νd=(Nd-1) / (NF-NC), where Nd, NF, and NC are the refractive indices of the Fraunhofer lines at the d-line (587.6 nm), F-line (486.1 nm), and C-line (656.3 nm).

[0161] An asterisk (*) next to a surface number indicates that the surface has an aspheric shape. The aspheric shape is expressed by the following formula, where x is the displacement in the optical axis direction at a position of height h from the optical axis relative to the apex of the surface, R is the paraxial radius of curvature, k is the conic constant, and Ai: (i=2,4,6,8…) are the aspheric coefficients of each order.

[0162]

number

[0163] In addition, the various data include focal length (mm), F-number, half angle of view (°), image height (mm), and the like.

[0164] (Numerical Example 1) Unit: mm Surface Data Surface number rd nd νd 1* 33.264 3.80 1.51633 64.1 2* 67.341 7.87 3 (Aperture) ∞ 3.61 4* -60.314 8.76 1.54658 55.9 5* -56.658 2.00 6* -178.356 4.14 1.54658 55.9 7* -278.259 5.36 8* -49.931 -5.36 9* -278.259 -4.14 1.54658 55.9 10* -178.356 -2.00 11* -56.658 2.00 12* -178.356 4.14 1.54658 55.9 13* -278.259 5.36 14* -49.931 2.35 1.54658 55.9 15* 19.782 11.00 16 ∞ 3.00 1.51633 64.1 17 ∞ 0.10 Image plane ∞ Aspheric Data Front page K = 0.00000e+00 A 4= 1.75368e-06 A 6=-2.08107e-09 2nd side K = 0.00000e+00 A 4=-1.06144e-06 A 6=-1.12963e-08 Page 4 K = 0.00000e+00 A 2=-5.47088e-03 A 4=-1.57901e-05 A 6= 2.13974e-08 A 8= 7.49429e-12 Page 5 K = 0.00000e+00 A 4=-3.35715e-06 A 6= 5.58849e-09 A 8=-1.34412e-11 A10= 1.23184e-14 A12=-8.60860e-21 Page 6 K = 0.00000e+00 A 4= 2.67533e-05 A 6=-6.60403e-08 A 8= 8.83817e-11 A10=-3.54229e-13 A12= 2.37426e-16 Page 7 K = 0.00000e+00 A 4= 2.21090e-05 A 6=-4.76083e-08 A 8= 9.17449e-11 A10=-3.35061e-13 Page 8 K = 0.00000e+00 A 4=-8.37494e-07 A 6= 9.41948e-10 A 8= 8.14789e-12 A10=-1.12477e-13 A12= 3.58736e-16 Page 9 K = 0.00000e+00 A 4= 2.21090e-05 A 6=-4.76083e-08 A 8= 9.17449e-11 A10=-3.35061e-13 Page 10 K = 0.00000e+00 A 4= 2.67533e-05 A 6=-6.60403e-08 A 8= 8.83817e-11 A10=-3.54229e-13 A12= 2.37426e-16 Page 11 K = 0.00000e+00 A 4=-3.35715e-06 A 6= 5.58849e-09 A 8=-1.34412e-11 A10= 1.23184e-14 A12=-8.60860e-21 Side 12 K = 0.00000e+00 A 4= 2.67533e-05 A 6=-6.60403e-08 A 8= 8.83817e-11 A10=-3.54229e-13 A12= 2.37426e-16 Page 13 K = 0.00000e+00 A 4= 2.21090e-05 A 6=-4.76083e-08 A 8= 9.17449e-11 A10=-3.35061e-13 Side 14 K = 0.00000e+00 A 4=-8.37494e-07 A 6= 9.41948e-10 A 8= 8.14789e-12 A10=-1.12477e-13 A12= 3.58736e-16 Page 15 K = 0.00000e+00 A 2=-4.12994e-02 A 4=-1.43658e-05 A 6=-9.85889e-09 A 8=-1.01161e-10 Various data Focal length 48.00 F-number 1.50 Half angle of view: 24.26 Image height 21.64 BF 0.10 d17 0.10 (Numerical Example 2) Unit: mm Surface Data Surface number rd nd νd 1* -92.915 1.80 1.85400 40.4 2* 275.875 0.20 3 66.286 7.72 1.70482 29.8 4 -107.417 2.08 5(Aperture) ∞ 4.87 6 -67.525 1.50 1.93012 34.8 7 ∞ 1.00 1.51633 64.1 8 ∞ 0.10 1.51633 64.1 9∞3.86 1.90686 34.6 10 -110.546 -3.86 11 ∞ -0.10 1.51633 64.1 12 ∞ -1.00 1.51633 64.1 13∞1.00 14 ∞ 0.10 1.51633 64.1 15 ∞ 3.86 1.90686 34.6 16 -110.546 1.69 1.96278 27.0 17 116.994 1.00 18* 54.224 1.20 1.82754 38.6 19* 45.694 1.20 20 33.649 6.69 1.49703 81.6 21 -154.042 1.74 22 -55.180 6.50 1.58935 64.1 23 -20.730 3.00 1.80508 46.8 24 -64.377 0.10 25 -70.837 5.04 1.49701 81.6 26 -29.198 -0.10 27 131.017 2.02 1.61588 65.3 28* -250.495 9.40 29∞3.00 1.51633 64.1 30 ∞ 0.10 Image plane ∞ Aspheric Data Front page K = 0.00000e+00 A 4=-4.06466e-06 A 6= 1.03932e-08 A 8=-1.67472e-11 A10= 1.02529e-14 2nd side K = 0.00000e+00 A 4=-3.12852e-06 A 6= 1.11218e-08 A 8=-2.12628e-11 A10= 1.94691e-14 A12=-6.84758e-18 Side 18 K = 0.00000e+00 A 4= 2.10433e-05 A 6=-2.77702e-08 Page 19 K = 0.00000e+00 A 4= 2.40984e-05 A 6=-2.49256e-08 Page 28 K = 0.00000e+00 A 4= 7.07409e-06 A 6=-7.48712e-09 A 8= 2.28141e-11 A10=-3.65416e-14 Various data Focal length 32.00 F-number: 0.75 Half angle of view: 24.37 Image height 14.50 BF 0.10 d30 0.10 (Numerical Example 3) Unit: mm Surface Data Surface number rd nd νd 1* -161.627 1.80 1.85400 40.4 2* 82.516 0.20 3 51.999 6.47 1.73854 38.7 4 -66.398 4.96 5(Aperture) ∞ 2.19 6 -115.094 1.50 1.72916 54.7 7 100.330 2.62 1.49092 67.6 8 ∞ 0.10 1.51633 50.0 9 ∞ 2.00 1.51633 64.1 10∞ -2.00 11 ∞ -0.10 1.51633 50.0 12 ∞ -2.62 1.49092 67.6 13 100.330 2.62 14 ∞ 0.10 1.51633 50.0 15 ∞ 2.00 1.51633 64.1 16 ∞ 1.70 1.84297 43.7 17 44.276 2.26 18 809.825 2.59 1.72916 54.7 19 -101.774 1.20 20 47.329 3.62 1.52211 77.5 21 941.218 2.45 22 -47.172 9.50 1.53844 75.1 23 -23.955 2.00 1.90571 37.6 24 -39.180 0.10 25 71.664 5.31 1.59522 67.7 26 -64.902 9.40 27 ∞ 3.00 1.51633 64.1 28∞0.10 Image plane ∞ Aspheric Data Front page K = 0.00000e+00 A 4=-1.82053e-06 A 6= 1.07157e-09 2nd side K = 0.00000e+00 A 4= 1.11630e-06 A 6= 2.22067e-09 Various data Focal length 32.00 F-number: 0.95 Half angle of view: 24.38 Image height 14.50 BF 0.10 d28 0.10 (Numerical Example 4) Unit: mm Surface Data Surface number rd nd νd 1 38.604 1.80 1.59522 67.7 2 21.733 10.42 3 -2098.480 1.00 1.73273 54.3 4 51.623 0.20 5 36.753 4.79 1.55917 44.3 6 -101.671 2.00 7 -69.648 1.20 1.59522 67.7 8 66.757 2.17 1.69895 30.1 9 426.308 1.50 10(Aperture) ∞ 6.23 11 30.285 6.34 1.49700 81.5 12 -105.796 0.10 13 230.558 2.11 1.49700 81.5 14 -161.563 7.56 15* -101.727 1.50 1.85035 35.9 16 ∞ 4.56 1.49700 81.5 17 -44.954 1.97 1.85407 36.5 18 -105.745 -1.97 19 -44.954 -4.56 1.49700 81.5 20∞4.56 21 -44.954 1.97 1.85407 36.5 22 -105.745 0.00 23 -105.745 3.45 1.87153 42.0 24 -36.678 0.10 25* 121.884 2.00 1.85087 43.0 26* 78.991 1.11 27 -210.514 1.20 1.84666 23.8 28 252.666 0.10 29 47.461 4.09 2.00330 28.3 30 260.763 9.40 31∞0.00 32∞0.00 33 ∞ 3.00 1.51633 64.1 34∞0.11 Image plane ∞ Aspheric Data Page 15 K = 0.00000e+00 A 4=-8.84207e-06 A 6=-1.26449e-08 Page 25 K = 0.00000e+00 A 4=-6.31962e-05 A 6= 2.28241e-08 Page 26 K = 0.00000e+00 A 4=-6.21297e-05 A 6= 4.62364e-08 Various data Focal length 21.65 21.65 21.65 F-number 0.95 0.95 0.95 Half angle of view 33.81 33.81 33.81 Image height 14.50 14.50 14.50 BF 0.11 0.11 0.11 d34 0.11 0.11 0.11 (Numerical Example 5) Unit: mm Surface Data Surface number rd nd νd 1 -109.185 1.50 1.67510 32.4 2 -1210.137 0.20 3* 34.632 6.56 1.63323 50.6 4* -186.241 0.30 5(Aperture) ∞ 5.89 6 -60.428 1.50 1.63270 47.5 7 761.621 0.10 8 181.467 1.50 1.49758 82.4 9∞11.55 1.49402 82.0 10 -65.604 2.00 11* -86.397 1.00 2.00330 28.3 12 -110.085 -1.00 13* -86.397 -2.00 14 -65.604 -11.55 1.49402 82.0 15∞11.55 16 -65.604 2.00 17* -86.397 1.00 2.00330 28.3 18 -110.085 1.00 19 115.140 1.71 1.63640 63.1 20* 3508.933 1.44 21∞1.50 1.51633 64.1 22∞0.10 Image plane ∞ Aspheric Data 3rd page K = 0.00000e+00 A 4= 1.63267e-07 A 6= 2.93219e-09 Side 4 K = 0.00000e+00 A 4= 1.17377e-06 A 6= 8.47197e-10 A 8=-1.15699e-12 A10=-4.32516e-15 Page 11 K = 0.00000e+00 A 4=-2.19247e-06 A 6=-2.62246e-09 A 8= 2.21713e-12 A10=-2.22878e-14 A12= 1.58408e-17 Page 13 K = 0.00000e+00 A 4=-2.19247e-06 A 6=-2.62246e-09 A 8= 2.21713e-12 A10=-2.22878e-14 A12= 1.58408e-17 Page 17 K = 0.00000e+00 A 4=-2.19247e-06 A 6=-2.62246e-09 A 8= 2.21713e-12 A10=-2.22878e-14 A12= 1.58408e-17 Page 20 K = 0.00000e+00 A 4= 2.63824e-05 A 6=-1.06717e-07 Various data Focal length 32.00 F-number: 0.95 Half angle of view: 24.38 Image height 14.50 BF 0.10 d22 0.10 (Numerical Example 6) Unit: mm Surface Data Surface number rd nd νd 1 -81.190 3.00 1.56404 71.6 2 -178.691 0.94 3 84.160 14.20 1.54726 46.3 4 -109.712 3.90 5(Aperture) ∞ 13.27 6 -47.777 1.50 1.60342 38.0 7 ∞ 3.43 1.88300 40.8 8 -214.922 2.26 9* -144.806 3.50 1.59522 67.7 10 -101.352 -3.50 11* -144.806 -2.26 12 -214.922 -3.43 1.88300 40.8 13∞3.43 14 -214.922 2.26 15* -144.806 3.50 1.59522 67.7 16 -101.352 4.35 1.81057 25.1 17 279.559 1.00 18 68.860 8.79 1.72916 54.7 19* -135.440 4.25 20 58.135 6.52 1.50599 80.0 21 -114.882 1.00 22∞3.00 1.51633 64.1 23∞0.10 Image plane ∞ Aspheric Data 9th page K = 0.00000e+00 A 4=-8.77810e-07 A 6= 1.97233e-11 A 8=-1.93497e-13 A10= 2.59713e-16 A12=-1.33641e-19 Page 11 K = 0.00000e+00 A 4=-8.77810e-07 A 6= 1.97233e-11 A 8=-1.93497e-13 A10= 2.59713e-16 A12=-1.33641e-19 Page 15 K = 0.00000e+00 A 4=-8.77810e-07 A 6= 1.97233e-11 A 8=-1.93497e-13 A10= 2.59713e-16 A12=-1.33641e-19 Page 19 K = 0.00000e+00 A 4= 1.32990e-07 A 6= 1.09167e-09 A 8=-5.37842e-13 A10= 2.07993e-16 Various data Focal length 32.00 F-number: 0.55 Half angle of view: 24.38 Image height 14.50 BF 0.10 d23 0.10 (Numerical Example 7) Unit: mm Surface Data Surface number rd nd νd 1 132.020 1.80 1.52841 76.5 2 23.495 3.81 3* 34.705 2.50 1.54658 55.9 4* 24.842 5.79 5 33.997 3.04 1.84666 23.8 6 51.145 12.17 7 27.031 5.79 1.48749 70.4 8 -127.810 0.30 9(Aperture) ∞ 4.51 10* -97.461 1.50 1.72916 54.7 11 183.806 1.00 12 ∞ 1.00 1.51633 64.1 13 ∞ 2.62 1.48749 70.2 14 -62.885 2.00 1.85025 30.1 15* -100.173 -2.00 16 -62.885 -2.62 1.48749 70.2 17 ∞ -1.00 1.51633 64.1 18∞1.00 19∞2.62 1.48749 70.2 20 -62.885 2.00 1.85025 30.1 21* -100.173 2.15 22 -71.168 3.71 1.49700 81.5 23 -26.476 0.50 24 -49.336 1.20 1.84666 23.8 25 1246.886 0.10 26* 44.977 7.21 1.85400 40.4 27* -51.137 9.40 28∞3.00 1.51633 64.1 29∞0.10 Image plane ∞ Aspheric Data 3rd page K = 0.00000e+00 A 4= 2.80058e-05 A 6=-1.86749e-08 A 8= 5.41443e-12 A10= 5.11302e-14 Side 4 K = 0.00000e+00 A 4= 2.71319e-05 A 6=-2.40373e-08 Side 10 K = 0.00000e+00 A 4= 1.80747e-06 A 6= 5.34299e-10 Page 15 K = 0.00000e+00 A 4= 2.89798e-06 A 6= 4.44896e-09 A 8= 2.67425e-12 Page 21 K = 0.00000e+00 A 4= 2.89798e-06 A 6= 4.44896e-09 A 8= 2.67425e-12 Page 26 K = 0.00000e+00 A 4=-2.06753e-06 A 6= 7.40511e-09 A 8= 2.47090e-11 Page 27 K = 0.00000e+00 A 4= 1.08328e-05 A 6=-2.04810e-08 A 8= 1.01300e-10 A10=-9.40040e-14 Various data Focal length 17.38 17.38 17.38 F-number 0.95 0.95 0.95 Half angle of view 39.84 39.84 39.84 Image height 14.50 14.50 14.50 BF 0.10 0.10 0.10 d29 0.10 0.10 0.10 (Numerical Example 8) Unit: mm Surface Data Surface number rd nd νd 1* -409.789 1.80 1.85400 40.4 2* 42.180 0.20 3 40.979 3.54 1.84666 23.8 4 122.998 1.00 5 96.345 1.92 2.00100 29.1 6 41.243 6.48 1.81600 46.6 7 -118.059 0.50 8(Aperture) ∞ 13.69 9 ∞ 1.00 1.51633 64.1 10 ∞ 0.10 1.51633 40.0 11∞2.72 1.82115 24.1 12 -105.501 -2.72 13 ∞ -0.10 1.51633 40.0 14 ∞ -1.00 1.51633 64.1 15∞1.00 16 ∞ 0.10 1.51633 40.0 17 ∞ 2.72 1.82115 24.1 18 -105.501 1.70 1.92119 24.0 19* 39.788 4.68 20 -36.572 2.13 1.84666 23.8 21 -35.086 1.00 22 91.120 7.28 1.49700 81.6 23 -28.563 2.00 1.87070 40.7 24 -173.578 0.10 25* 39.262 8.74 1.58913 61.1 26* -44.520 9.40 27 ∞ 3.00 1.51633 64.1 28∞0.10 Image plane ∞ Aspheric Data Front page K = 0.00000e+00 A 4= 4.43125e-08 A 6= 8.19697e-10 2nd side K = 0.00000e+00 A 4= 1.51907e-06 A 6= 1.25991e-09 Page 19 K = 0.00000e+00 A 4=-5.63465e-07 A 6=-1.32044e-09 A 8=-6.59630e-12 A10=-3.66076e-15 Page 25 K = 0.00000e+00 A 4= 5.89089e-08 A 6= 7.14844e-09 Page 26 K = 0.00000e+00 A 4= 9.86729e-06 A 6=-5.58092e-09 A 8= 3.90470e-11 A10=-5.62801e-14 Various data Focal length 32.00 32.00 32.00 F-number 0.95 0.95 0.95 Half angle of view 24.38 24.38 24.38 Image height 14.50 14.50 14.50 BF 0.10 0.10 0.10 d28 0.10 0.10 0.10 (Numerical Example 9) Unit: mm Surface Data Surface number rd nd νd 1* 8.184 1.64 1.54658 55.9 2* 33.051 4.17 3(Aperture) ∞ 0.60 4* -43.951 1.60 1.54658 55.9 5* 564.166 1.26 6* -7.524 0.30 1.54658 55.9 7* -10.919 0.95 8* -26.449 0.90 1.54658 55.9 9* -15.162 0.95 10* -9.626 -0.95 11* -15.162 -0.90 1.54658 55.9 12* -26.449 -0.95 13* -10.919 0.95 14* -26.449 0.90 1.54658 55.9 15* -15.162 0.95 16* -9.626 0.35 1.54658 55.9 17* -6.872 0.03 18 ∞ 0.43 1.51633 64.1 19∞0.10 Image plane ∞ Aspheric Data Front page K = 0.00000e+00 A 2=-2.92248e-02 A 4=-1.66006e-04 A 6= 1.48542e-06 A 8=-3.34281e-08 A10= 2.02751e-10 A12= 1.57208e-12 2nd side K = 0.00000e+00 A 4= 7.63633e-05 A 6= 5.33636e-06 A 8=-1.52003e-07 A10= 3.33154e-09 A12=-2.42253e-11 Side 4 K = 0.00000e+00 A 4=-3.88719e-04 A 6=-1.52411e-05 A 8= 2.17573e-06 A10=-1.53277e-07 5th page K = 0.00000e+00 A 4=-2.17211e-04 A 6= 1.28090e-05 A 8=-8.94365e-07 Page 6 K = 0.00000e+00 A 4=-5.58108e-04 A 6= 1.87674e-05 A 8=-1.36199e-06 Side 7 K = 0.00000e+00 A 4=-3.42153e-04 A 6= 6.88122e-06 A 8=-2.36999e-07 A10=-8.92100e-10 A12= 2.97739e-13 Page 8 K = 0.00000e+00 A 4= 5.15689e-05 A 6=-1.88653e-05 A 8= 3.12701e-07 A10=-1.02106e-08 A12= 5.08818e-11 Page 9 K = 0.00000e+00 A 4= 1.00441e-04 A 6=-2.22495e-05 A 8= 4.90051e-07 A10=-9.61925e-09 Page 10 K = 0.00000e+00 A 4=-4.29042e-05 A 6= 3.45895e-06 A 8=-2.86769e-08 A10=-2.33169e-09 A12= 2.61879e-11 A14=-1.75383e-14 A16=-2.25865e-16 Page 11 K = 0.00000e+00 A 4= 1.00441e-04 A 6=-2.22495e-05 A 8= 4.90051e-07 A10=-9.61925e-09 Page 12 K = 0.00000e+00 A 4= 5.15689e-05 A 6=-1.88653e-05 A 8= 3.12701e-07 A10=-1.02106e-08 A12= 5.08818e-11 Page 13 K = 0.00000e+00 A 4=-3.42153e-04 A 6= 6.88122e-06 A 8=-2.36999e-07 A10=-8.92100e-10 A12= 2.97739e-13 Page 14 K = 0.00000e+00 A 4= 5.15689e-05 A 6=-1.88653e-05 A 8= 3.12701e-07 A10=-1.02106e-08 A12= 5.08818e-11 Page 15 K = 0.00000e+00 A 4= 1.00441e-04 A 6=-2.22495e-05 A 8= 4.90051e-07 A10=-9.61925e-09 Page 16 K = 0.00000e+00 A 4=-4.29042e-05 A 6= 3.45895e-06 A 8=-2.86769e-08 A10=-2.33169e-09 A12= 2.61879e-11 A14=-1.75383e-14 A16=-2.25865e-16 Page 17 K = 0.00000e+00 A 2= 7.65763e-03 A 4= 1.70301e-03 A 6=-2.74630e-05 A 8= 2.26084e-07 Various data Focal length 7.74 F-number 1.40 Half angle of view: 45.66 Image height 7.92 BF 0.10 d19 0.10 (Numerical Example 10) Unit: mm Surface Data Surface number rd nd νd 1* 34.495 3.34 1.51633 64.1 2* 75.497 (variable) 3(Aperture) ∞ 4.31 4* -69.221 3.66 1.54658 55.9 5* -51.980 (variable) 6* 117.370 4.32 1.54658 55.9 7* 166.054 3.48 8* 111.755 -3.48 9* 166.054 -4.32 1.54658 55.9 10* 117.370 (variable) 11* -51.980 (variable) 12* 117.370 4.32 1.54658 55.9 13* 166.054 3.48 14* 111.755 3.04 1.54658 55.9 15* 34.800 (variable) 16 ∞ 3.00 1.51633 64.1 17 ∞ 0.10 Image plane ∞ Aspheric Data Front page K = 0.00000e+00 A 4=-1.74929e-06 A 6=-8.62843e-10 2nd side K = 0.00000e+00 A 4=-4.07821e-06 A 6=-7.23767e-10 Side 4 K = 0.00000e+00 A 2=-1.22787e-02 A 4=-1.83823e-06 A 6= 2.70135e-08 A 8=-5.09885e-11 5th page K = 0.00000e+00 A 4=-2.15470e-06 A 6= 4.98429e-09 A 8=-3.38806e-11 A10= 1.31569e-13 A12=-2.13965e-16 Page 6 K = 0.00000e+00 A 4=-1.56713e-07 A 6=-6.36987e-08 A 8= 8.88377e-11 A10=-2.64136e-13 A12= 2.14791e-16 Page 7 K = 0.00000e+00 A 4= 3.08711e-06 A 6=-4.36485e-08 A 8= 1.39724e-11 A10= 2.33549e-15 Page 8 K = 0.00000e+00 A 2=-1.54062e-02 A 4=-1.12202e-06 A 6= 1.18269e-10 A 8= 5.81600e-12 A10=-5.88663e-15 A12= 1.86539e-18 Page 9 K = 0.00000e+00 A 4= 3.08711e-06 A 6=-4.36485e-08 A 8= 1.39724e-11 A10= 2.33549e-15 Page 10 K = 0.00000e+00 A 4=-1.56713e-07 A 6=-6.36987e-08 A 8= 8.88377e-11 A10=-2.64136e-13 A12= 2.14791e-16 Page 11 K = 0.00000e+00 A 4=-2.15470e-06 A 6= 4.98429e-09 A 8=-3.38806e-11 A10= 1.31569e-13 A12=-2.13965e-16 Page 12 K = 0.00000e+00 A 4=-1.56713e-07 A 6=-6.36987e-08 A 8= 8.88377e-11 A10=-2.64136e-13 A12= 2.14791e-16 Page 13 K = 0.00000e+00 A 4= 3.08711e-06 A 6=-4.36485e-08 A 8= 1.39724e-11 A10= 2.33549e-15 Side 14 K = 0.00000e+00 A 2=-1.54062e-02 A 4=-1.12202e-06 A 6= 1.18269e-10 A 8= 5.81600e-12 A10=-5.88663e-15 A12= 1.86539e-18 Page 15 K = 0.00000e+00 A 2=-3.00572e-02 A 4=-1.07875e-05 A 6=-1.07802e-08 A 8= 4.04651e-13 Various data Focal length 48.00 F-number 1.50 Half angle of view: 24.26 Image height 21.64 BF 0.10 Object distance INF 480 400 d2 12.67 12.67 12.67 d5 3.08 2.37 2.00 d10 -3.08 -2.37 -2.00 d11 3.08 2.37 2.00 d15 11.00 20.26 23.79 d17 0.10 -6.12 -8.05 (Numerical Example 11) Unit: mm Surface Data Surface number rd nd νd 1 43.050 2.48 1.49700 81.5 2 122.119 5.62 3(Aperture) ∞ 0.99 4 -72.690 1.50 1.51680 64.2 5 -2719.444 2.91 1.49700 81.5 6 -71.844 14.08 7* -84.641 2.00 1.77250 49.5 8 -127.982 -2.00 9* -85.016 -14.08 10 -71.844 -2.91 1.49700 81.5 11 -2719.444 2.91 12 -71.844 14.08 13* -84.641 2.00 1.77250 49.5 14 -127.982 1.70 1.80518 25.4 15 -755.115 1.00 16 50.885 4.16 1.49700 81.5 17 -142.624 2.00 18 ∞ 1.50 1.51633 64.1 19∞0.10 Image plane ∞ Aspheric Data Side 7 K = 0.00000e+00 A 4=-1.27170e-06 A 6= 1.09638e-09 A 8=-1.59118e-11 A10= 6.69227e-14 A12=-1.11236e-16 9th page K = 0.00000e+00 A 4=-1.27170e-06 A 6= 1.09638e-09 A 8=-1.59118e-11 A10= 6.69227e-14 A12=-1.11236e-16 Page 13 K = 0.00000e+00 A 4=-1.27170e-06 A 6= 1.09638e-09 A 8=-1.59118e-11 A10= 6.69227e-14 A12=-1.11236e-16 Various data Focal length 45.00 F-number 2.00 Half angle of view: 16.72 Image height 13.52 BF 0.10 d19 0.10 (Numerical Example 12) Unit: mm Surface Data Surface number rd nd νd 1 -64.414 1.70 1.80400 46.6 2 -89.821 0.20 3 37.669 7.98 1.51823 58.9 4 -115.201 3.69 5(Aperture) ∞ 2.18 6 -105.027 1.50 1.83481 42.7 7 -577.086 7.48 8 132.568 1.50 1.49700 81.5 9 ∞ 1.81 1.83481 42.7 10 -134.855 2.00 11* -54.249 2.00 1.85400 40.4 12 -102.974 -2.00 13* -54.249 -2.00 14 -134.855 -1.81 1.83481 42.7 15∞1.81 16 -135.405 2.00 17* -54.249 2.00 1.85400 40.4 18 -102.974 1.70 2.00330 28.3 19 220.682 1.16 20 -170.532 3.24 1.49700 81.5 21 -36.082 1.20 22 57.215 4.96 1.80420 46.5 23 -81.669 9.40 24 ∞ 3.00 1.51633 64.1 25∞0.10 Image plane ∞ Aspheric Data Page 11 K = 0.00000e+00 A 4=-2.98007e-06 A 6= 5.44403e-09 A 8=-5.81960e-11 A10= 2.52878e-13 A12=-4.19387e-16 Page 13 K = 0.00000e+00 A 4=-2.98007e-06 A 6= 5.44403e-09 A 8=-5.81960e-11 A10= 2.52878e-13 A12=-4.19387e-16 Page 17 K = 0.00000e+00 A 4=-2.98007e-06 A 6= 5.44403e-09 A 8=-5.81960e-11 A10= 2.52878e-13 A12=-4.19387e-16 Various data Focal length 32.00 F-number: 0.95 Half angle of view: 24.38 Image height 14.50 BF 0.10 d25 0.10 (Numerical Example 13) Unit: mm Surface Data Surface number rd nd νd 1 212.715 2.00 1.49700 81.5 2 117.564 3.05 1.68948 31.0 3 296.551 23.72 4 242.548 2.89 1.84666 23.8 5 101.330 2.49 6 -110.931 2.00 1.91082 35.2 7 913.868 1.15 8(Aperture) ∞ 0.30 9 60.164 3.22 1.80518 25.5 10 ∞ 4.95 1.48749 70.2 11 -52.664 2.31 12* -56.420 2.00 1.85400 40.4 13 -101.670 -2.00 14* -56.420 -2.31 15 -52.664 -4.95 1.48749 70.2 16∞4.95 17 -52.664 2.31 18* -56.420 2.00 1.85400 40.4 19 -101.670 1.70 1.77250 49.6 20 37.111 1.12 21 42.372 9.37 1.51680 64.2 22* -27.818 1.20 23 40.818 4.10 1.49700 81.5 24 1004.153 9.40 25∞3.00 1.51633 64.1 26∞0.10 Image plane ∞ Aspheric Data Side 12 K = 0.00000e+00 A 4=-2.56220e-06 A 6=-1.16511e-09 A 8=-8.21450e-12 A10= 2.52195e-14 A12=-4.26110e-17 Side 14 K = 0.00000e+00 A 4=-2.56220e-06 A 6=-1.16511e-09 A 8=-8.21450e-12 A10= 2.52195e-14 A12=-4.26110e-17 Side 18 K = 0.00000e+00 A 4=-2.56220e-06 A 6=-1.16511e-09 A 8=-8.21450e-12 A10= 2.52195e-14 A12=-4.26110e-17 Page 22 K = 0.00000e+00 A 4= 2.04785e-06 A 6=-8.15703e-09 Various data Focal length 32.00 F-number: 0.95 Half angle of view: 24.38 Image height 14.50 BF 0.10 d26 0.10 (Numerical Example 14) Unit: mm Surface Data Surface number rd nd νd 1 -100.067 2.00 1.48749 70.2 2 -340.582 2.93 3 79.292 11.08 1.54072 47.2 4 -128.708 7.22 5(Aperture) ∞ 7.19 6 -64.631 2.00 1.60342 38.0 7 ∞ 2.53 1.83481 42.7 8 -260.842 4.82 9* -82.704 3.50 1.53996 59.5 10 -90.589 -3.50 11* -82.704 -4.82 12 -260.842 -2.53 1.83481 42.7 13∞2.53 14 -260.842 4.82 15* -82.704 3.50 1.53996 59.5 16 -90.589 1.72 1.84666 23.8 17 -1015.139 1.72 18 47.324 7.42 1.64000 60.2 19* -96.561 3.49 20 51.514 5.39 1.55352 71.7 21 -114.495 1.06 22∞3.00 1.51633 64.1 23∞0.10 Image plane ∞ Aspheric Data 9th page K = 0.00000e+00 A 4=-8.31478e-07 A 6=-2.74307e-10 A 8= 1.58841e-13 A10= 2.42540e-17 A12=-1.36738e-19 Page 11 K = 0.00000e+00 A 4=-8.31478e-07 A 6=-2.74307e-10 A 8= 1.58841e-13 A10= 2.42540e-17 A12=-1.36738e-19 Page 15 K = 0.00000e+00 A 4=-8.31478e-07 A 6=-2.74307e-10 A 8= 1.58841e-13 A10= 2.42540e-17 A12=-1.36738e-19 Page 19 K = 0.00000e+00 A 4= 2.54086e-06 A 6=-5.50287e-10 A 8= 1.66150e-12 A10= 7.92260e-18 Various data Focal length 32.00 F-number: 0.55 Half angle of view: 24.38 Image height 14.50 BF 0.10 d23 0.10 (Numerical Example 15) Unit: mm Surface Data Surface number rd nd νd 1* 52.287 5.84 1.58573 59.7 2* 135.265 6.51 3(Aperture) ∞ 3.11 4 -106.453 2.00 1.53775 74.7 5 -114.505 13.32 1.56732 42.8 6 -117.115 15.96 7* -59.265 2.00 1.51742 52.2 8 -104.966 -2.00 9* -59.265 -15.96 10 -117.043 -13.32 1.56732 42.8 11 -114.430 13.32 12 -117.043 15.96 13* -59.265 2.00 1.51742 52.2 14 -104.966 1.70 1.51742 52.4 15 -85.497 1.00 16* 526.394 2.84 1.85400 40.4 17* -148.323 4.44 18 ∞ 1.50 1.51633 64.1 19∞0.10 Image plane ∞ Aspheric Data Front page K = 0.00000e+00 A 4= 3.18032e-07 A 6= 2.80240e-10 A 8=-6.47939e-14 A10= 3.10952e-16 2nd side K = 0.00000e+00 A 4=-1.64643e-07 A 6=-1.26010e-10 Side 7 K = 0.00000e+00 A 4=-7.44307e-07 A 6=-5.79334e-10 A 8= 2.09678e-14 A10=-7.96117e-16 A12= 2.86214e-19 9th page K = 0.00000e+00 A 4=-7.44307e-07 A 6=-5.79334e-10 A 8= 2.09678e-14 A10=-7.96117e-16 A12= 2.86214e-19 Page 13 K = 0.00000e+00 A 4=-7.44307e-07 A 6=-5.79334e-10 A 8= 2.09678e-14 A10=-7.96117e-16 A12= 2.86214e-19 Page 16 K = 0.00000e+00 A 4=-4.65984e-05 A 6=-1.36407e-07 Page 17 K = 0.00000e+00 A 4=-5.41008e-05 A 6=-5.41946e-08 Various data Focal length 100.00 F-number 2.00 Half angle of view: 7.70 Image height 13.52 BF 0.10 d19 0.10 (Numerical Example 16) Unit: mm Surface Data Surface number rd nd νd 1 62.002 6.87 1.61997 63.9 2 374.246 20.78 3(Aperture) ∞ 2.62 4 -101.769 1.50 1.88300 40.8 5 ∞ 12.45 1.65160 58.5 6 -80.971 2.00 7* -92.486 2.41 1.85400 40.4 8 -169.778 -2.41 9* -92.486 -2.00 10 -80.971 -12.45 1.65160 58.5 11∞12.45 12 -80.971 2.00 13* -92.486 2.41 1.85400 40.4 14 -169.778 6.36 1.49700 81.5 15 -59.903 14.27 16 ∞ 3.00 1.51633 64.1 17 ∞ 0.10 Image plane ∞ Aspheric Data Side 7 K = 0.00000e+00 A 4=-8.49441e-07 A 6= 4.42583e-10 A 8=-2.29922e-12 A10= 3.41916e-15 A12=-2.00408e-18 9th page K = 0.00000e+00 A 4=-8.49441e-07 A 6= 4.42583e-10 A 8=-2.29922e-12 A10= 3.41916e-15 A12=-2.00408e-18 Page 13 K = 0.00000e+00 A 4=-8.49441e-07 A 6= 4.42583e-10 A 8=-2.29922e-12 A10= 3.41916e-15 A12=-2.00408e-18 Various data Focal length 52.00 F-number: 0.95 Half angle of view: 14.58 Image height 13.52 BF 0.10 d17 0.10 (Numerical Example 17) Unit: mm Surface Data Surface number rd nd νd 1 45.051 2.00 2.00100 29.1 2 46.817 6.45 3* 35.316 5.10 1.51633 64.1 4 448.833 1.29 5(Aperture) ∞ 8.73 6 -34.039 1.71 1.49700 81.5 7 -37.495 0.10 8 -222.409 1.50 2.00100 29.1 9∞4.62 1.48749 70.2 10 -46.732 1.50 11* -40.684 2.00 1.85400 40.4 12 -98.403 -2.00 13* -40.684 -1.50 14 -46.732 -4.62 1.48749 70.2 15∞4.62 16 -46.732 1.50 17* -40.684 2.00 1.85400 40.4 18 -98.404 1.00 19 144.816 5.66 1.88300 40.8 20 -42.677 9.40 21∞3.00 1.51633 64.1 22∞0.10 Image plane ∞ Aspheric Data 3rd page K = 0.00000e+00 A 4= 1.01631e-06 A 6=-2.30048e-09 A 8= 2.71764e-11 A10=-5.99857e-14 A12= 7.06294e-17 Page 11 K = 0.00000e+00 A 4=-4.23437e-06 A 6= 4.07555e-09 A 8=-6.70601e-11 A10= 2.79579e-13 A12=-4.68393e-16 Page 13 K = 0.00000e+00 A 4=-4.23437e-06 A 6= 4.07555e-09 A 8=-6.70601e-11 A10= 2.79579e-13 A12=-4.68393e-16 Page 17 K = 0.00000e+00 A 4=-4.23437e-06 A 6= 4.07555e-09 A 8=-6.70601e-11 A10= 2.79579e-13 A12=-4.68393e-16 Various data Focal length 32.00 F-number: 0.95 Half angle of view: 24.38 Image height 14.50 BF 0.10 d22 0.10 (Numerical Example 18) Unit: mm Surface Data Surface number rd nd νd 1 48.707 1.50 1.84666 23.8 2* 46.185 5.77 3 38.164 2.00 1.78470 26.3 4 79.648 1.86 5(Aperture) ∞ 2.07 6 -62.601 2.37 1.59522 67.7 7 ∞ 3.87 1.52841 76.5 8 -51.351 2.07 9* -44.034 2.00 1.95375 32.3 10 -71.635 -2.00 11* -44.034 -2.07 12 -51.351 -3.87 1.52841 76.5 13∞3.87 14 -51.351 2.07 15* -44.034 2.00 1.95375 32.3 16 -71.635 4.69 1.72916 54.7 17* -29.692 1.00 18 35.258 6.70 1.49700 81.5 19 -97.953 3.39 20∞3.00 1.51633 64.1 21∞0.10 Image plane ∞ Aspheric Data 2nd side K = 0.00000e+00 A 4=-1.80322e-06 A 6=-4.85921e-09 9th page K = 0.00000e+00 A 4=-5.53212e-06 A 6=-1.00677e-08 A 8= 2.07899e-12 A10=-6.64077e-14 A12=-8.05438e-17 Page 11 K = 0.00000e+00 A 4=-5.53212e-06 A 6=-1.00677e-08 A 8= 2.07899e-12 A10=-6.64077e-14 A12=-8.05438e-17 Page 15 K = 0.00000e+00 A 4=-5.53212e-06 A 6=-1.00677e-08 A 8= 2.07899e-12 A10=-6.64077e-14 A12=-8.05438e-17 Page 17 K = 0.00000e+00 A 4=-3.18242e-06 A 6=-2.57579e-08 A 8= 7.82406e-11 A10=-2.38554e-13 Various data Focal length 21.65 F-number 0.90 Half angle of view: 33.82 Image height 14.50 BF 0.10 d21 0.10 (Numerical Example 19) Unit: mm Surface Data Surface number rd nd νd 1* 34.741 3.12 1.51633 64.1 2* 70.145 (variable) 3 (Aperture) ∞ 3.67 4* -87.357 6.37 1.54658 55.9 5* -50.934 (variable) 6* -51.069 4.35 1.54658 55.9 7* -55.512 5.11 8* -48.144 -5.11 9* -55.512 -4.35 1.54658 55.9 10* -51.069 (variable) 11* -50.934 (variable) 12* -51.069 4.35 1.54658 55.9 13* -55.512 5.11 14* -48.144 1.70 1.54658 55.9 15* 22.265 (variable) 16 ∞ 3.00 1.51633 64.1 17 ∞ 0.10 Image plane ∞ Aspheric Data Front page K = 0.00000e+00 A 4= 2.05760e-06 A 6=-1.20695e-09 A 8= 1.87087e-11 A10=-3.04451e-14 A12=-3.38066e-18 2nd side K = 0.00000e+00 A 4= 8.53439e-07 A 6=-3.77007e-09 A 8= 1.13209e-11 A10=-4.09934e-14 A12= 2.20382e-17 Side 4 K = 0.00000e+00 A 2=-9.94614e-03 A 4=-1.13659e-05 A 6= 1.70344e-08 A 8= 1.55013e-11 A10= 1.01486e-14 5th page K = 0.00000e+00 A 4=-1.98602e-06 A 6= 1.24590e-09 A 8= 7.15980e-12 A10=-7.27344e-14 Page 6 K = 0.00000e+00 A 4= 1.74651e-05 A 6=-3.72923e-08 A 8=-5.19580e-11 A10= 7.83608e-14 A12=-7.61217e-16 Side 7 K = 0.00000e+00 A 4= 1.25192e-05 A 6=-2.18272e-08 A 8= 2.39426e-11 A10=-1.99465e-13 Page 8 K = 0.00000e+00 A 4=-1.52761e-07 A 6= 1.51824e-10 A 8=-4.67105e-13 A10=-1.43466e-14 A12= 6.59523e-17 Page 9 K = 0.00000e+00 A 4= 1.25192e-05 A 6=-2.18272e-08 A 8= 2.39426e-11 A10=-1.99465e-13 Page 10 K = 0.00000e+00 A 4= 1.74651e-05 A 6=-3.72923e-08 A 8=-5.19580e-11 A10= 7.83608e-14 A12=-7.61217e-16 Page 11 K = 0.00000e+00 A 4=-1.98602e-06 A 6= 1.24590e-09 A 8= 7.15980e-12 A10=-7.27344e-14 Page 12 K = 0.00000e+00 A 4= 1.74651e-05 A 6=-3.72923e-08 A 8=-5.19580e-11 A10= 7.83608e-14 A12=-7.61217e-16 Page 13 K = 0.00000e+00 A 4= 1.25192e-05 A 6=-2.18272e-08 A 8= 2.39426e-11 A10=-1.99465e-13 Page 14 K = 0.00000e+00 A 4=-1.52761e-07 A 6= 1.51824e-10 A 8=-4.67105e-13 A10=-1.43466e-14 A12= 6.59523e-17 Page 15 K = 0.00000e+00 A 2=-3.67253e-02 A 4=-6.47218e-06 A 6=-1.64802e-08 A 8=-4.65932e-11 Various data Focal length 47.99 F-number 1.50 Half angle of view: 24.26 Image height 21.64 BF 0.10 Object distance INF 480 275 d2 11.58 9.08 6.48 d 5 2.00 2.83 3.39 d10 -2.00 -2.83 -3.39 d11 2.00 2.83 3.39 d15 11.00 12.67 14.70 d17 0.10 -4.96 -9.09 (Numerical Example 20) Unit: mm Surface Data Surface number rd nd νd 1 -95.586 3.00 1.91082 35.2 2 -213.920 2.23 3 66.966 8.02 1.61293 37.0 4 -123.603 7.39 5(Aperture) ∞ 4.18 6 -76.270 1.00 1.79950 42.3 7 ∞ 3.02 1.78800 47.5 8 -126.465 2.00 9* -69.935 2.00 1.85400 40.4 10 -101.262 0.00 11 -101.262 0.00 12 -101.262 -2.00 1.85400 40.4 13* -69.935 -2.00 14 -126.465 -3.02 1.78800 47.5 15∞3.02 16 -126.421 2.00 17* -69.935 2.00 1.85400 40.4 18 -101.262 0.00 19 -101.262 1.70 1.91082 35.2 20 182.675 1.00 21 46.813 10.35 1.49700 81.6 22* -73.680 1.20 23 79.825 6.53 1.49700 81.5 24 -49.719 9.40 25∞3.00 1.51633 64.1 26∞0.10 Image plane ∞ Aspheric Data 9th page K = 0.00000e+00 A 4=-1.02932e-06 A 6= 1.71899e-10 A 8=-1.82378e-12 A10= 4.42535e-15 A12=-4.22552e-18 Page 13 K = 0.00000e+00 A 4=-1.02932e-06 A 6= 1.71899e-10 A 8=-1.82378e-12 A10= 4.42535e-15 A12=-4.22552e-18 Page 17 K = 0.00000e+00 A 4=-1.02932e-06 A 6= 1.71899e-10 A 8=-1.82378e-12 A10= 4.42535e-15 A12=-4.22552e-18 Page 22 K = 0.00000e+00 A 4= 4.77769e-06 A 6= 3.78844e-09 Various data Focal length 32.00 F-number: 0.70 Half angle of view: 24.38 Image height 14.50 BF 0.10 d26 0.10 (Numerical Example 21) Unit: mm Surface Data Surface number rd nd νd 1 41.943 11.40 1.48749 70.2 2 716.633 4.73 3* 201.736 2.40 1.77250 49.5 4* 72.349 5.98 5(Aperture) ∞ 9.41 6 ∞ 3.12 1.51742 52.4 7 -125.229 2.34 8 -89.374 2.00 1.88300 40.8 9 -151.660 -2.00 10 -89.374 -2.34 11 -125.229 -3.12 1.51742 52.4 12∞3.12 13 -125.229 2.34 14 -89.374 2.00 1.88300 40.8 15 -151.660 4.00 16* -51.495 2.50 1.54400 56.0 17* -65.237 0.15 18 69.697 9.65 1.48749 70.2 19 -44.228 0.11 20 2922.340 5.40 1.90525 35.0 21 182.622 13.20 22∞3.00 1.51633 64.1 23∞0.10 Image plane ∞ Aspheric Data 3rd page K = 0.00000e+00 A 4= 5.29083e-06 A 6=-9.38486e-09 A 8= 8.37198e-12 A10=-3.53430e-15 Side 4 K = 0.00000e+00 A 4= 7.53551e-06 A 6=-8.80710e-09 A 8= 8.79233e-12 A10=-3.43617e-15 Page 16 K = 0.00000e+00 A 4= 1.27331e-05 A 6=-1.42063e-08 Page 17 K = 0.00000e+00 A 4= 1.65139e-05 A 6=-1.03897e-08 A 8=-5.14026e-12 A10= 8.65167e-15 Various data Focal length 50.00 F-number: 0.96 Half angle of view: 23.40 Image height 21.64 BF 0.10 d23 0.10 (Numerical Example 22) Unit: mm Surface Data Surface number rd nd νd 1 173.495 2.00 1.88300 40.8 2 49.123 0.03 3* 37.190 2.00 1.54000 56.0 4* 41.815 0.50 5 43.296 8.70 1.64769 33.8 6 103.465 3.02 7(Aperture) ∞ 2.00 8 46.811 11.04 1.49700 81.5 9 -84.883 5.74 10 -74.092 1.50 1.65160 58.5 11 ∞ 4.81 1.51633 64.1 12 -65.199 1.87 13* -63.950 2.00 1.85400 40.4 14* -114.321 -2.00 15* -63.950 -1.87 16 -65.199 -4.81 1.51633 64.1 17∞4.81 18 -65.199 1.87 19* -63.950 2.00 1.85400 40.4 20* -114.321 0.20 21 ∞ 1.00 1.51633 64.1 22∞5.44 1.48749 70.2 23 -52.217 12.00 24 ∞ 3.00 1.51633 64.1 25∞0.10 Image plane ∞ Aspheric Data 3rd page K = 0.00000e+00 A 4=-6.28932e-06 A 6=-1.79799e-08 A 8=-1.23977e-11 A10= 3.86980e-14 Side 4 K = 0.00000e+00 A 4=-3.97301e-06 A 6=-1.70340e-08 A 8=-1.09235e-11 A10= 4.30624e-14 Page 13 K = 0.00000e+00 A 4=-1.56151e-06 A 6= 3.94324e-11 A 8= 3.89519e-12 A10=-1.21217e-14 A12= 1.18319e-17 Side 14 K = 0.00000e+00 A 4= 4.92297e-08 A 6= 6.76632e-10 Page 15 K = 0.00000e+00 A 4=-1.56151e-06 A 6= 3.94324e-11 A 8= 3.89519e-12 A10=-1.21217e-14 A12= 1.18319e-17 Page 19 K = 0.00000e+00 A 4=-1.56151e-06 A 6= 3.94324e-11 A 8= 3.89519e-12 A10=-1.21217e-14 A12= 1.18319e-17 Page 20 K = 0.00000e+00 A 4= 4.92297e-08 A 6= 6.76632e-10 Various data Focal length 35.00 F-number 1.00 Half angle of view: 31.72 Image height 21.64 BF 0.10 d25 0.10 (Numerical Example 23) Unit: mm Surface Data Surface number rd nd νd 1 43.558 1.80 1.69895 30.1 2* 60.509 3.98 3 121.002 2.41 1.49700 81.5 4 -507.521 6.78 5(Aperture) ∞ 2.36 6 -124.482 1.50 2.00330 28.3 7 ∞ 1.50 1.49700 81.5 8 402.886 3.43 9* -465.811 2.00 1.49700 81.5 10 -103.041 -2.00 11* -465.811 -3.43 12 402.886 -1.50 1.49700 81.5 13∞1.50 14 402.886 3.43 15* -465.811 2.00 1.49700 81.5 16 -103.041 1.70 1.88300 40.8 17 -299.030 1.44 18 -106.107 6.87 1.48749 70.4 19* -35.070 1.20 20 32.823 6.31 1.49700 81.5 21 480.969 6.81 22∞3.00 1.51633 64.1 23∞0.10 Image plane ∞ Aspheric Data 2nd side K = 0.00000e+00 A 4= 4.08957e-07 A 6=-5.56282e-10 9th page K = 0.00000e+00 A 4=-2.15617e-06 A 6=-3.25248e-09 A 8= 1.70004e-11 A10=-9.65529e-14 A12= 1.62524e-16 Page 11 K = 0.00000e+00 A 4=-2.15617e-06 A 6=-3.25248e-09 A 8= 1.70004e-11 A10=-9.65529e-14 A12= 1.62524e-16 Page 15 K = 0.00000e+00 A 4=-2.15617e-06 A 6=-3.25248e-09 A 8= 1.70004e-11 A10=-9.65529e-14 A12= 1.62524e-16 Page 19 K = 0.00000e+00 A 4= 4.46773e-07 A 6=-5.83941e-09 A 8= 5.31116e-12 A10=-1.07179e-14 Various data Focal length 31.99 F-number 1.20 Half angle of view: 24.38 Image height 14.50 BF 0.10 d23 0.10 (Numerical Example 24) Unit: mm Surface Data Surface number rd nd νd 1 -1663.968 2.00 1.61800 63.4 2 71.473 0.30 3* 92.922 2.04 1.54000 56.0 4* 108.037 0.50 5 39.338 15.64 1.48749 70.2 6 1004.404 1.68 7(Aperture) ∞ 2.33 8 60.041 10.92 1.49700 81.5 9 -49.535 0.30 10 -71.257 5.59 1.69680 55.5 11 -140.988 5.89 12 -91.635 1.50 1.59551 39.2 13∞1.60 14* 213.232 2.30 1.77250 49.5 15* 576.812 1.26 16 -124.828 -1.26 17* 576.812 -2.30 1.77250 49.5 18* 213.232 -1.60 19∞1.60 20* 213.232 2.30 1.77250 49.5 21* 576.812 1.26 22 -124.828 1.50 1.98612 16.5 23 ∞ 1.00 1.51633 64.1 24∞0.10 25 140.590 5.21 1.79360 37.1 26 -85.259 10.33 27 ∞ 3.00 1.51633 64.1 28∞0.10 Image plane ∞ Aspheric Data 3rd page K = 0.00000e+00 A 4= 1.29859e-06 A 6= 6.82258e-09 A 8= 1.75850e-11 A10=-2.68142e-14 Side 4 K = 0.00000e+00 A 4= 4.27604e-06 A 6= 9.79087e-09 A 8= 1.77416e-11 A10=-1.97887e-14 Side 14 K = 0.00000e+00 A 4=-6.23100e-06 A 6= 5.29938e-09 A 8=-4.53625e-11 A10= 6.33782e-14 Page 15 K = 0.00000e+00 A 4=-4.46191e-06 A 6= 3.27854e-09 A 8=-3.42859e-11 A10= 4.89042e-14 Page 17 K = 0.00000e+00 A 4=-4.46191e-06 A 6= 3.27854e-09 A 8=-3.42859e-11 A10= 4.89042e-14 Side 18 K = 0.00000e+00 A 4=-6.23100e-06 A 6= 5.29938e-09 A 8=-4.53625e-11 A10= 6.33782e-14 Page 20 K = 0.00000e+00 A 4=-6.23100e-06 A 6= 5.29938e-09 A 8=-4.53625e-11 A10= 6.33782e-14 Page 21 K = 0.00000e+00 A 4=-4.46191e-06 A 6= 3.27854e-09 A 8=-3.42859e-11 A10= 4.89042e-14 Various data Focal length 35.50 F-number: 0.95 Half angle of view: 31.36 Image height 21.64 BF 0.10 d28 0.10 (Numerical Example 25) Unit: mm Surface Data Surface number rd nd νd 1 43.323 11.34 1.48749 70.2 2 1026.458 6.87 3* 224.417 2.40 1.77250 49.5 4* 67.659 5.58 5(Aperture) ∞ 7.24 6 ∞ 2.00 1.51633 64.1 7 ∞ 1.50 8 323.649 2.47 1.65943 60.8 9 -369.996 1.71 10 -111.236 2.00 1.89293 39.3 11 -157.686 -2.00 12 -111.236 -1.71 13 -369.996 -2.47 1.65943 60.8 14 323.649 -1.50 15∞1.50 16 323.649 2.47 1.65943 60.8 17 -369.996 1.71 18 -111.236 2.00 1.89293 39.3 19 -157.686 0.10 20∞1.80 1.51633 64.1 21∞2.95 22* -35.701 2.50 1.54400 56.0 23* -42.066 0.15 24 75.163 9.49 1.48749 70.2 25 -41.912 0.11 26 -125.469 6.08 1.88300 40.8 27 -4397.925 11.79 28∞3.00 1.51633 64.1 29∞0.10 Image plane ∞ Aspheric Data 3rd page K = 0.00000e+00 A 4= 1.29798e-06 A 6=-3.96015e-09 A 8= 4.15359e-12 A10=-2.08355e-15 Side 4 K = 0.00000e+00 A 4= 3.17673e-06 A 6=-3.76681e-09 A 8= 5.14754e-12 A10=-3.01761e-15 Page 22 K = 0.00000e+00 A 4= 1.81465e-05 A 6= 3.61890e-10 A 8=-5.09761e-11 A10= 5.10749e-14 Page 23 K = 0.00000e+00 A 4= 2.06653e-05 A 6= 2.60284e-09 A 8=-4.72922e-11 A10= 4.87368e-14 Various data Focal length 50.00 F-number: 0.95 Half angle of view: 23.40 Image height 21.64 BF 0.10 d29 0.10 (Numerical Example 26) Unit: mm Surface Data Surface number rd nd νd 1* 34.442 3.39 1.51633 64.1 2* 49.387 14.11 3(Aperture) ∞ 8.00 4* -40.752 1.50 1.54658 55.9 5* -56.972 1.11 6* 59.695 6.31 1.54658 55.9 7* 67.405 4.60 8* -49.479 -4.60 9* 67.405 -6.31 1.54658 55.9 10* 59.695 -1.11 11* -56.972 1.11 12* 59.695 6.31 1.54658 55.9 13* 67.405 4.60 14* -49.479 1.87 1.54658 55.9 15* -39.271 11.00 16 ∞ 3.00 1.51633 64.1 17 ∞ 0.10 Image plane ∞ Aspheric Data Front page K = 0.00000e+00 A 4= 1.88779e-07 A 6= 3.81432e-09 A 8=-6.92099e-12 A10= 1.47763e-14 A12= 2.09285e-18 2nd side K = 0.00000e+00 A 4= 3.34279e-07 A 6= 4.78843e-09 A 8=-1.29872e-11 A10= 2.79285e-14 A12=-1.08478e-17 Side 4 K = 0.00000e+00 A 4=-1.15373e-07 A 6= 1.61379e-08 A 8=-1.23993e-10 A10= 2.56881e-13 A12= 1.87005e-16 5th page K = 0.00000e+00 A 4=-4.26715e-06 A 6=-7.78873e-09 A 8= 2.53451e-11 A10=-3.37826e-13 A12= 9.95687e-16 Page 6 K = 0.00000e+00 A 4=-9.31759e-06 A 6=-5.59292e-08 A 8= 1.47485e-10 A10=-4.23025e-13 A12=-3.93468e-16 Page 7 K = 0.00000e+00 A 4=-4.47037e-06 A 6=-6.44026e-08 A 8= 2.05905e-10 A10=-6.27518e-13 A12= 7.31725e-16 Page 8 K = 0.00000e+00 A 4=-1.37402e-06 A 6= 6.20006e-09 A 8=-1.27963e-11 A10= 6.01445e-14 A12=-1.20501e-16 Page 9 K = 0.00000e+00 A 4=-4.47037e-06 A 6=-6.44026e-08 A 8= 2.05905e-10 A10=-6.27518e-13 A12= 7.31725e-16 Page 10 K = 0.00000e+00 A 4=-9.31759e-06 A 6=-5.59292e-08 A 8= 1.51573e-10 A10=-4.08206e-13 A12=-2.41308e-16 Page 11 K = 0.00000e+00 A 4=-4.26715e-06 A 6=-7.78873e-09 A 8= 2.53451e-11 A10=-3.37826e-13 A12= 9.95687e-16 Page 12 K = 0.00000e+00 A 4=-9.31759e-06 A 6=-5.59292e-08 A 8= 1.47485e-10 A10=-4.23025e-13 A12=-3.93468e-16 Page 13 K = 0.00000e+00 A 4=-4.47037e-06 A 6=-6.44026e-08 A 8= 2.05905e-10 A10=-6.27518e-13 A12= 7.31725e-16 Side 14 K = 0.00000e+00 A 4=-1.37402e-06 A 6= 6.20006e-09 A 8=-1.27963e-11 A10= 6.01445e-14 A12=-1.20501e-16 Page 15 K = 0.00000e+00 A 4=-3.44872e-06 A 6= 2.97587e-08 A 8=-1.68641e-10 A10= 5.42072e-13 A12=-7.60286e-16 Various data Focal length 50.00 F-number 1.50 Half angle of view: 23.40 Image height 21.64 BF 0.10 d17 0.10 Table 1 shows the values ​​of each condition in each embodiment.

[0165] [Table 1]

[0166] Next, with reference to Fig. 55, a digital still camera (imaging device) using the optical system of each embodiment as an imaging optical system will be described. Fig. 15 is an explanatory diagram of an imaging device 6 equipped with the optical system of each embodiment. In Fig. 15, 4 is a camera body, and 3 is an imaging optical system corresponding to any one of the optical systems OS1 to OS26 of each embodiment. 5 is an imaging element (photoelectric conversion element) such as a CCD sensor or a CMOS sensor that is built into the camera body 4 and receives an optical image formed by the imaging optical system 3 and photoelectrically converts it. The camera body 4 may be a so-called single-lens reflex camera having a quick return mirror, or a so-called mirrorless camera not having a quick return mirror.

[0167] The optical system of each embodiment can be used in imaging cameras and distance detection cameras for smartphones, interchangeable lenses for interchangeable lens cameras, fixed lens cameras, and film cameras with lenses (disposable cameras). It may also be used in camera viewfinders and XR devices for, for example, line-of-sight detection, biometric recognition, and facial expression recognition. It may also be used for external world recognition applications such as XR devices and automatic robots.

[0168] According to each embodiment, it is possible to provide a small-sized optical system and an imaging device having high optical performance over a wide focus range.

[0169] The disclosure of each embodiment includes the following configuration. (Configuration 1) An optical system having a first refractive lens, a first transmissive-reflective surface, a quarter-wave plate, and a second transmissive-reflective surface, which are arranged in this order from an object side to an image side, During focusing, the first transmissive-reflective surface moves in the optical axis direction, During focusing, the first refractive lens does not move or the distance between the first refractive lens and the first transmission-reflection surface in the optical axis direction changes; 13. An optical system, comprising: the first refractive lens separated from both the first transmissive-reflective surface and the second transmissive-reflective surface. (Configuration 2) An optical system having a first refractive lens, a first transmission-reflection surface, a quarter-wave plate, a second transmission-reflection surface, and a second refractive lens, which are arranged in this order from an object side to an image side, During focusing, the first transmissive-reflective surface moves in the optical axis direction, During focusing, the second refractive lens does not move or the distance between the second refractive lens and the first transmissive-reflective surface in the optical axis direction changes; 13. An optical system, comprising: the second refractive lens separated from both the first transmissive-reflective surface and the second transmissive-reflective surface. (Configuration 3) 3. The optical system according to configuration 1 or 2, wherein the first refractive lens is a lens in the optical system closest to the object side. (Configuration 4) When the refractive power of the optical system on the object side of the first transmitting-reflecting surface is φfr and the power of the optical system is φtotal, -1.00≦φfr / φtotal≦0.42 4. The optical system according to any one of configurations 1 to 3, wherein the following condition is satisfied: (Configuration 5) When the axial marginal ray is reflected by the second transmissive-reflective surface, the distance from the optical axis to the reflection point in a direction perpendicular to the optical axis is Hm2, and the focal length of the optical system is f. 0.15≦Hm2 / f≦3.00 5. The optical system according to any one of configurations 1 to 4, wherein the following condition is satisfied: (Configuration 6) When the distance from the surface of the optical system closest to the object side to the entrance pupil of the optical system is dpupil and the focal length of the optical system is f, 0.0≦dpupil / f≦2.0 6. The optical system according to any one of configurations 1 to 5, wherein the following condition is satisfied: (Configuration 7) When the effective diameter of the first transmitting and reflecting surface is Pm1 and the entrance pupil diameter of the optical system is Ppupil, 0.6≦Pm1 / Ppupil≦2.0 7. The optical system according to any one of configurations 1 to 6, wherein the following condition is satisfied: (Configuration 8) When the F-number of the optical system is Fno, 0.5≦Fno≦2.5 8. The optical system according to any one of configurations 1 to 7, wherein the following condition is satisfied: (Configuration 9) a third refractive lens disposed closer to the object side than the first transmission-reflection surface, the third refractive lens being separated from the first transmission-reflection surface and moving integrally with the first transmission-reflection surface during focusing; When the refractive power on the object side of the lens group that moves integrally with the first transmissive-reflective surface during focusing is φb, -1.00≦φb / φtotal≦0.70 9. The optical system according to any one of configurations 1 to 8, wherein the following condition is satisfied: (Configuration 10) When the amount of movement when focusing from infinity to a distance 10 times the focal length of the optical system is |Δdf|, 0.005≦|Δdf| / f / Fno≦1.000 10. The optical system according to any one of configurations 1 to 9, wherein the following condition is satisfied: (Configuration 11) 11. The optical system according to any one of configurations 1 to 10, wherein the distance between the first transmissive-reflective surface and the second transmissive-reflective surface changes during focusing. (Configuration 12) Further comprising an aperture stop; 12. The optical system according to any one of configurations 1 to 11, wherein, during focusing, the aperture stop moves in the optical axis direction integrally with the first transmitting and reflecting surface. (Configuration 13) 13. The optical system described in any one of configurations 1 to 12, wherein a fourth refractive lens arranged outside the area between the first transmissive reflective surface and the second transmissive reflective surface moves in the optical axis direction during focusing. (Configuration 14) 14. The optical system according to any one of configurations 1 to 13, wherein during focusing, each of the first transmissive-reflective surface and the second transmissive-reflective surface does not rotate by 0.5° or more about the optical axis. (Configuration 15) When the smaller of the open angle of the first transmissive-reflective surface and the open angle of the second transmissive-reflective surface is θm (°), 0.0≦|θm|≦8.0 15. The optical system according to any one of configurations 1 to 14, characterized in that the following conditional expression is satisfied: (Configuration 16) 16. The optical system according to any one of configurations 1 to 15, wherein at least one of the first transmissive-reflective surface and the second transmissive-reflective surface has both surfaces cemented together with glass or resin. (Configuration 17) 17. The optical system according to any one of configurations 1 to 16, wherein at least one of the first transmissive-reflective surface and the second transmissive-reflective surface is a spherical surface. (Configuration 18) 18. The optical system according to any one of configurations 1 to 17, further comprising a vibration isolation group arranged on the object side of the first transmitting and reflecting surface. (Configuration 19) Let β be the lateral magnification of the lens unit on the image side of the second transmitting-reflecting surface, 0.6≦β≦1.5 19. The optical system according to configuration 18, wherein the following condition is satisfied: (Configuration 20) 20. An imaging device comprising the optical system according to any one of configurations 1 to 19 and an imaging element.

[0170] Although the preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of the gist of the present invention. [Explanation of symbols]

[0171] OS1~OS26 Optical system HM1 1st transmissive reflective surface HM2 2nd transmissive reflective surface QWP 1 / 4 wave plate L1 First refractive lens L2 Second refractive lens

Claims

1. An optical system having a first transmissive reflective surface, a second transmissive reflective surface disposed on the image side of the first transmissive reflective surface, and a lens disposed on the object side of the first transmissive reflective surface or on the image side of the second transmissive reflective surface, During focusing, the first transmission / reflection surface moves in the optical axis direction. The optical system is characterized in that the lens is separated from both the first transmission reflective surface and the second transmission reflective surface.

2. The optical system according to claim 1, characterized in that the lens is the lens closest to the object in the optical system.

3. When the refractive power of the optical system on the object side of the first transmission / reflection surface is φfr and the power of the optical system is φtotal, -1.00 ≤ φfr / φtotal ≤ 0.42 The optical system according to claim 1, characterized in that it satisfies the following condition.

4. When the on-axial marginal ray is reflected by the second transmissive reflective surface, the distance from the optical axis to the reflection point in a direction perpendicular to the optical axis is Hm2, and the focal length of the optical system is f. 0.15 ≤ Hm² / f ≤ 3.00 The optical system according to claim 1, characterized in that it satisfies the following condition.

5. When the distance from the object-side surface of the optical system to the entrance pupil of the optical system is dpupil, and the focal length of the optical system is f, 0.0 ≤ dpupil / f ≤ 2.0 The optical system according to claim 1, characterized in that it satisfies the following condition.

6. When the effective diameter of the first transmissive reflective surface is Pm1 and the entrance pupil diameter of the optical system is Ppupil, 0.6 ≤ Pm1 / Ppupil ≤ 2.0 The optical system according to claim 1, characterized in that it satisfies the following condition.

7. When the F-number of the optical system is denoted as Fno, 0.5 ≤ Fno ≤ 2.5 The optical system according to claim 1, characterized in that it satisfies the following condition.

8. The system further comprises a group of lenses positioned on the object side of the first transmissive reflective surface, separated from the first transmissive reflective surface, and moving integrally with the first transmissive reflective surface during focusing. When focusing, if the refractive force on the object side is φb and the power of the optical system is φtotal, compared to the lens group that moves integrally with the first transmission / reflection surface, -1.00 ≤ φb / φtotal ≤ 0.70 The optical system according to claim 1, characterized in that it satisfies the following condition.

9. When focusing from infinity to a distance of 10 times the focal length of the optical system, the amount of movement of the first transmitted reflective surface is |Δdf|, the focal length of the optical system is f, and the F-number of the optical system is Fno. 0.005≦|Δdf| / f / Fno≦1.000 The optical system according to claim 1, characterized in that it satisfies the following condition.

10. The optical system according to claim 1, characterized in that the distance between the first transmissive reflective surface and the second transmissive reflective surface changes during focusing.

11. It further has an aperture diaphragm, The optical system according to claim 1, characterized in that, during focusing, the aperture diaphragm moves integrally with the first transmission and reflection surface in the direction of the optical axis.

12. The optical system according to claim 1, further comprising a lens disposed outside the region between the first transmissive reflective surface and the second transmissive reflective surface, and moving in the direction of the optical axis during focusing.

13. The optical system according to claim 1, characterized in that, during focusing, neither the first transmissive reflective surface nor the second transmissive reflective surface rotates by 0.5° or more around the optical axis.

14. When the smaller of the opening angles of the first transmissive reflective surface and the opening angle of the second transmissive reflective surface is θm (°), 0.0≦|θm|≦8.0 The optical system according to claim 1, characterized in that it satisfies the following condition.

15. The optical system according to claim 1, characterized in that a lens made of glass or resin is bonded to at least one of the first transmissive reflective surface or the second transmissive reflective surface.

16. The optical system according to claim 1, characterized in that at least one of the first transmissive reflective surface or the second transmissive reflective surface is spherical.

17. The optical system according to claim 1, further comprising a vibration isolation group positioned on the object side of the first transmission and reflection surface.

18. When the lateral magnification of the lens group on the image side of the second transmission / reflection surface is β, ０．６≦β≦１．５ The optical system according to claim 17, characterized in that it satisfies the following condition.

19. An imaging device characterized by having the optical system described in claim 1 and an image sensor.

Images