Optical system, image projection device, and imaging device

Abstract

The present disclosure is an optical system having therein a middle imaging position MI conjugate with each of an enlargement conjugate point on an enlargement side and a reduction conjugate point on a reduction side, the optical system comprising: an enlargement optical system Op having a plurality of lens elements L1-L15 and positioned more on the enlargement side than the middle imaging position MI; and a relay optical system Ol having a plurality of lens elements L16-L28 and positioned more on the reduction side than the middle imaging position MI. The enlargement optical system Op is stationary with respect to the reduction conjugate point when zooming. The relay optical system Ol includes a plurality of mobile lens groups G2-G5 which can move independently in the optical axis direction when zooming. The most-reduction-side mobile lens group G5, which is positioned most on the reduction side among the plurality of mobile lens groups, has a negative refractive power.

Description

Technical Field

[0001] The present disclosure relates to an optical system that forms an intermediate image. The present disclosure also relates to an image projection device and an imaging device using such an optical system.

Background Art

[0002] An optical system with an intermediate imaging method has the advantage of being able to achieve a wide-angle projection with a short focal length and a large screen, but the overall length of the optical system tends to increase. Therefore, the optical system becomes heavy, and when a part of the optical system is mounted outside the housing of the image projection device main body, the optical system may tilt with respect to the device main body due to the moment acting on the center of gravity, and the optical performance may deteriorate.

[0003] Patent Document 1 discloses a wide-angle imaging optical system, and the first lens L1a closest to the enlarged conjugate point has the largest aperture. The first lens L1a has aspherical surfaces on both sides and a rather complex shape.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The present disclosure provides an optical system in which the lens is made wider, the effective diameter of the lens is reduced, the optical system and the zoom mechanism are made smaller and lighter. The present disclosure also provides an image projection device and an imaging device using such an optical system.

Means for Solving the Problems

[0006] The lens system according to the present disclosure is an optical system having an intermediate imaging position that is conjugate to the enlarged conjugate point on the enlarged side and the reduced conjugate point on the reduced side, respectively, A magnification optical system having multiple lens elements and located on the magnification side from the intermediate imaging position, The system comprises a relay optical system having multiple lens elements and located on the reduction side from the intermediate imaging position, The magnifying optical system is fixed with respect to the reduced conjugate point during zooming. The relay optical system includes a plurality of movable lens groups that can move independently in the optical axis direction during zooming. The group of movable lenses located at the most reduced position among the aforementioned multiple movable lens groups has a negative refractive power.

[0007] Furthermore, the image projection device according to this disclosure comprises the optical system and an image forming element that generates an image to be projected onto a screen via the optical system.

[0008] Furthermore, the imaging device according to this disclosure comprises the optical system described above and an image sensor that receives the optical image formed by the optical system and converts it into an electrical image signal. [Effects of the Invention]

[0009] The lens system described herein allows for wider-angle lenses, reduced effective lens diameter, and miniaturization and weight reduction of the optical system and zoom mechanism. [Brief explanation of the drawing]

[0010] [Figure 1] A diagram showing the optical path at the wide-angle end of the zoom lens system in Example 1 at an object distance of 1100 mm. [Figure 2] Diagram showing the arrangement of the wide-angle end of the zoom lens system in Example 1 at an object distance of 1100 mm. [Figure 3] Longitudinal aberration diagram of the zoom lens system of Example 1 at an object distance of 1100 mm. [Figure 4] Longitudinal aberration diagram of the zoom lens system of Example 1 at object distances of 710 mm and 762 mm. [Figure 5] Longitudinal aberration diagram of the zoom lens system of Example 1 at object distances of 2842 mm and 3048 mm. [Figure 6]Layout diagram showing the optical path of the wide-angle end of the zoom lens system in Example 2 at an object distance of 1100 mm [Figure 7] Layout diagram of the wide-angle end of the zoom lens system in Example 2 at an object distance of 1100 mm [Figure 8] Longitudinal aberration diagram of the zoom lens system in Example 2 at an object distance of 1100 mm [Figure 9] Longitudinal aberration diagrams of the zoom lens system in Example 2 at object distances of 710 mm and 762 mm [Figure 10] Longitudinal aberration diagrams of the zoom lens system in Example 2 at object distances of 2842 mm and 3048 mm [Figure 11] Layout diagram showing the optical path of the wide-angle end of the zoom lens system in Example 3 at an object distance of 1100 mm [Figure 12] Layout diagram of the wide-angle end of the zoom lens system in Example 3 at an object distance of 1100 mm [Figure 13] Longitudinal aberration diagram of the zoom lens system in Example 3 at an object distance of 1100 mm [Figure 14] Longitudinal aberration diagrams of the zoom lens system in Example 3 at object distances of 710 mm and 762 mm [Figure 15] Longitudinal aberration diagrams of the zoom lens system in Example 3 at object distances of 2842 mm and 3048 mm [Figure 16] Layout diagram showing the optical path of the wide-angle end of the zoom lens system in Example 4 at an object distance of 1100 mm [Figure 17] Layout diagram of the wide-angle end of the zoom lens system in Example 4 at an object distance of 1100 mm [Figure 18] [[ID=3`6]]Longitudinal aberration diagram of the zoom lens system in Example 4 at an object distance of 1100 mm [Figure 19] Longitudinal aberration diagrams of the zoom lens system in Example 4 at object distances of 710 mm and 762 mm [Figure 20] Longitudinal aberration diagrams of the zoom lens system in Example 4 at object distances of 2842 mm and 3048 mm [Figure 21] Layout diagram showing the optical path of the wide-angle end of the zoom lens system in Example 5 at an object distance of 1100 mm [Figure 22]Diagram showing the arrangement of the wide-angle end of the zoom lens system in Example 5 at an object distance of 1100 mm. [Figure 23] Longitudinal aberration diagram of the zoom lens system of Example 5 at an object distance of 1100 mm. [Figure 24] Longitudinal aberration diagram of the zoom lens system of Example 5 at object distances of 710 mm and 762 mm. [Figure 25] Longitudinal aberration diagrams of the zoom lens system in Example 5 at object distances of 2842 mm and 3048 mm. [Figure 26] Block diagram showing an example of an image projection device related to this disclosure. [Figure 27] Block diagram showing an example of an imaging device related to this disclosure. [Modes for carrying out the invention]

[0011] The embodiments will be described in detail below, with reference to the drawings as appropriate. However, unnecessarily detailed explanations may be omitted. For example, detailed explanations of already well-known matters or redundant explanations of substantially identical configurations may be omitted. This is to avoid the following explanation becoming unnecessarily verbose and to facilitate understanding for those skilled in the art.

[0012] The applicant provides the accompanying drawings and the following description so that a person skilled in the art can fully understand the present disclosure, and not intends to limit the subject matter described in the claims.

[0013] The following describes various embodiments of the optical system according to this disclosure. In each embodiment, the case in which the optical system is used in a projector (an example of an image projection device) that projects image light of an original image S, which is obtained by spatially modulating incident light using an image forming element such as a liquid crystal or a DMD (digital micromirror device) based on an image signal, onto a screen will be described. That is, the optical system according to this disclosure can be used to enlarge an original image S on an image forming element located on the reduction side and project it onto a screen by placing a screen (not shown) on the extension of the enlargement side.

[0014] Furthermore, the optical system according to this disclosure can also be used to collect light emitted from an object located on the extension of the magnification side and to form an optical image of the object on the imaging surface of an image sensor located on the reduction side.

[0015] (Embodiment 1) Hereinafter, Embodiment 1 of this disclosure will be described with reference to Figures 1 to 25. Here, a zoom lens system will be described as an example of an optical system.

[0016] Figures 1, 6, 11, 16, and 21 are arrangement diagrams showing the optical path at the wide-angle end of the zoom lens system at an object distance of 1100 mm according to Examples 1 to 5. Figures 2, 7, 12, 17, and 22 are arrangement diagrams at the wide-angle end of the zoom lens system at an object distance of 1100 mm according to Examples 1 to 5. Figures 2(a), 7(a), 12(a), 17(a), and 22(a) show the lens arrangement diagram at the wide-angle end of the zoom lens system. Figures 2(b), 7(b), 12(b), 17(b), and 22(b) show the lens arrangement diagram at the intermediate position of the zoom lens system. Figures 2(c), 7(c), 12(c), 17(c), and 22(c) show the lens arrangement diagram at the telephoto end of the zoom lens system.

[0017] The wide-angle end is the shortest focal length state, where the entire system has the shortest focal length fw. The intermediate position is the intermediate focal length state between the wide-angle end and the telephoto end. The telephoto end is the longest focal length state, where the entire system has the longest focal length ft. Based on the focal length fw at the wide-angle end and the focal length ft at the telephoto end, the focal length fm at the intermediate position is defined as fm = √(fw × ft).

[0018] The zoom lens systems according to Examples 1 to 5 have an intermediate imaging position MI internally that is conjugate to the magnification conjugate point on the magnification side and the reduction conjugate point on the reduction side, respectively. A magnification optical system Op is positioned on the magnification side of the intermediate imaging position MI, and a relay optical system Ol is positioned on the reduction side of the intermediate imaging position MI. An optical element P is positioned on the reduction side of the relay optical system Ol.

[0019] In Example 1, the magnifying optical system Op is composed of the first lens element L1 to the 15th lens element L15 and includes surfaces 1 to 30 (see the numerical example below for surface numbers).

[0020] In Example 1, the relay optical system Ol includes the first lens group G1 to the sixth lens group G6. The first lens group G1 has positive power, is composed of the 16th lens element L16, and includes surfaces 31 to 32. The second lens group G2 has negative power, is composed of the 17th lens element L17, and includes surfaces 33 to 34. The third lens group G3 has positive power, is composed of the 18th lens element L18, and includes surfaces 35 to 36. The fourth lens group G4 has positive power, is composed of the 19th lens element L19 to the 21st lens element L21, and includes surfaces 37 to 42. The fifth lens group G5 has negative power, is composed of the 22nd lens element L22 to the 23rd lens element L23, and includes surfaces 43 to 47. The sixth lens group G6 has positive power, is composed of the 24th lens element L24 to the 28th lens element L28, and includes surfaces 48 to 57. The optical element P includes surfaces 58 to 59.

[0021] In Examples 2 to 5, the magnifying optical system Op is composed of a first lens element L1 to a 14th lens element L14 and includes surfaces 1 to 28.

[0022] In Examples 2 to 5, the relay optical system Ol includes the first lens group G1 to the sixth lens group G6. The first lens group G1 has positive power and is composed of the 15th lens element L15, including surfaces 29 to 30. The second lens group G2 has negative power and is composed of the 16th lens element L16, including surfaces 31 to 32. The third lens group G3 has positive power and is composed of the 17th lens element L17, including surfaces 33 to 34. The fourth lens group G4 has positive power and is composed of the 18th lens element L18 to the 20th lens element L20, including surfaces 35 to 40. The fifth lens group G5 has negative power and is composed of the 21st lens element L21 to the 22nd lens element L22, including surfaces 41 to 45. The sixth lens group G6 has positive power and consists of the 23rd lens element L23 to the 27th lens element L27, including surfaces 468 to 55. Optical element P includes surfaces 56 to 61.

[0023] The broken line arrows shown between each figure (a) and each figure (b) represent straight lines obtained by connecting the positions of the first lens group G1 to the sixth lens group G6 in the wide-angle end, intermediate position, and telephoto end, respectively, from top to bottom in the figures. The connections between the wide-angle end and the intermediate position, and between the intermediate position and the telephoto end, are simply straight lines and do not represent the actual movement of each lens group G1 to G6. The symbols (+) and (-) attached to the signs of each lens group G1 to G6 indicate the positive and negative power of each lens group G1 to G6.

[0024] The zoom lens systems according to Examples 1 to 5 may include, if necessary, a force lens group that adjusts focus when the object distance changes, and a field curvature correction lens group that corrects field curvature aberration after the focus lens group has adjusted focus. As an example, the zoom lens system according to Example 1 includes a first focus lens group FG1 composed of the 12th lens element L12 to the 15th lens element L15, and a second focus lens group FG2 composed of the 16th lens element L16. The zoom lens systems according to Examples 2 to 5 include a first focus lens group FG1 composed of the 11th lens element L11 to the 14th lens element L14, and a second focus lens group FG2 composed of the 15th lens element L15. These first focus lens group FG1 and second focus lens group FG2 can move independently along the optical axis during focusing.

[0025] In each figure, the image formation position on the enlarged side (i.e., the enlargement conjugate point) is located on the left, and the image formation position on the reduced side (i.e., the reduction conjugate point) is located on the right. In each figure, the straight line drawn on the farthest reduced side represents the position of the original image S, and the optical element P is located on the enlarged side of the original image S. The optical element P represents optical elements such as prisms for color separation and color synthesis, optical filters, parallel plate glass, quartz low-pass filters, and infrared cut filters.

[0026] In the zoom lens system according to Example 1, there are multiple air gaps between the first lens element L1, the 28th lens element L28, and the optical element P. In the zoom lens systems according to Examples 2 to 5, there are multiple air gaps between the first lens element L1, the 27th lens element L27, and the optical element P. The magnifying optical system Op has the longest air gap along the optical axis within the magnifying optical system. For example, in Example 1, as shown in Figure 2, the longest air gap is between the 11th lens element L11 and the 12th lens element L12. In Examples 2 to 5, as shown in Figures 7, 12, 17, and 22, the longest air gap is between the 10th lens element L10 and the 11th lens element L11. The magnifying optical system Op comprises a front group Opf located on the magnifying side of the longest air gap and a rear group Opr located on the reducing side of the longest air gap. The front group Opf and the rear group Opr may have one or more lens elements.

[0027] Figures 3, 8, 13, 18, and 23 show the longitudinal aberration diagrams of the zoom lens system according to Examples 1 to 5 at an object distance of 1100 mm. Figures 4, 9, 14, 19, and 24 show the longitudinal aberration diagrams of the zoom lens system according to Examples 1 to 5 at object distances of 710 mm and 762 mm. Figures 5, 10, 15, 20, and 25 show the longitudinal aberration diagrams of the zoom lens system according to Examples 1 to 5 at object distances of 2842 mm and 3048 mm. In each figure, (a), (b), and (c) show the longitudinal aberration diagrams of the zoom lens system at the wide-angle end, intermediate position, and telephoto end.

[0028] Each longitudinal aberration diagram shows, from left to right, spherical aberration (SA (mm)), astigmatism (AST (mm)), and distortion (DIS (%)). In the spherical aberration diagram, the vertical axis represents pupil height, the solid line represents the d-line, the short dashed line represents the F-line, and the long dashed line represents the C-line. In the astigmatism diagram, the vertical axis represents image height, the solid line represents the sagittal plane (indicated as s in the diagram), and the dashed line represents the meridional plane (indicated as m in the diagram). In the distortion diagram, the vertical axis represents image height. Furthermore, the distortion represents distortion relative to equidistant projection.

[0029] (Example 1) As shown in Figures 1 and 2, the zoom lens system according to Embodiment 1 comprises a magnification optical system Op and a relay optical system Ol. The magnification optical system Op is composed of a first lens element L1 to a fifteenth lens element L15. The magnification optical system Op includes a front group Opf and a rear group Opr.

[0030] The front group Opf of the magnifying optical system Op consists of lens elements L1 to L11 in order from the magnification side to the reduction side. The first lens element L1 has a negative meniscus shape with its convex surface facing the magnification side. The second lens element L2 has a negative meniscus shape with its convex surface facing the magnification side. The third lens element L3 has a negative meniscus shape with its convex surface facing the magnification side. The fourth lens element L4 has a biconcave shape. The fifth lens element L5 has a biconvex shape. The sixth lens element L6 has a positive meniscus shape with its convex surface facing the reduction side. The seventh lens element L7 has a positive meniscus shape with its convex surface facing the reduction side. The eighth lens element L8 has a biconcave shape. The ninth lens element L9 has a positive meniscus shape with its convex surface facing the reduction side. The tenth lens element L10 has a biconvex shape. The 11th lens element L11 has a negative meniscus shape with a convex surface facing the magnification side.

[0031] The rear group Opr of the magnifying optical system Op is composed of the 12th lens element L12 to the 15th lens element L15, in order from the magnification side to the reduction side. The 12th lens element L12 has a biconvex shape. The 13th lens element L13 has a positive meniscus shape with its convex surface facing the magnification side. The 14th lens element L14 has a positive meniscus shape with its convex surface facing the magnification side. The 15th lens element L15 has a negative meniscus shape with its convex surface facing the magnification side.

[0032] The relay optical system Ol is composed of lens elements L16 to L28 in order from the magnification side to the reduction side. Lens element L16 has a negative meniscus shape with its convex surface facing the reduction side. Lens element L17 has a biconcave shape. Lens element L18 has a positive meniscus shape with its convex surface facing the reduction side. Lens element L19 has a biconvex shape. Lens element L20 has a negative meniscus shape with its convex surface facing the reduction side. Lens element L21 has a biconvex shape. Lens element L22 has a positive meniscus shape with its convex surface facing the magnification side. Lens element L23 has a negative meniscus shape with its convex surface facing the magnification side. Lens element L24 has a biconcave shape. Lens element L25 has a biconvex shape. Lens element L26 has a biconvex shape. The 27th lens element L27 has a negative meniscus shape with its convex surface facing the magnification side. The 28th lens element L28 has a biconvex shape.

[0033] The relay optical system Ol consists of, in order from the magnification side to the reduction side, a first lens group G1 (L16) with positive power, a second lens group G2 (L17) with negative power, a third lens group G3 (L18) with positive power, a fourth lens group G4 (L19~L21) with positive power, a fifth lens group G5 (L22~L23) with negative power, and a sixth lens group G6 (L24~L28) with positive power. During zooming, the magnification optical system Op and the sixth lens group G6 are fixed relative to the reduction conjugate point. The first to fifth lens groups G1 to G5 may be displaced independently along the optical axis, or at least one of the first to fifth lens groups G1 to G5 may be fixed relative to the reduction conjugate point.

[0034] An intermediate imaging position MI is located between the 15th lens element L15 and the 16th lens element L16. Furthermore, aperture A is positioned between the 22nd lens element L22 and the 23rd lens element L23. On the reduction side of the relay optical system Ol, an optical element P with zero optical power is positioned.

[0035] (Examples 2-5) As shown in Figures 6, 7, 11, 12, 16, 17, 21, and 22, the zoom lens systems according to Examples 2 to 5 include a magnification optical system Op and a relay optical system Ol. The magnification optical system Op is composed of a first lens element L1 to a fourteenth lens element L14. The magnification optical system Op includes a front group Opf and a rear group Opr.

[0036] The front group Opf of the magnifying optical system Op is composed of the first lens element L1 to the tenth lens element L10, in order from the magnification side to the reduction side. The first lens element L1 has a negative meniscus shape with its convex surface facing the magnification side. The second lens element L2 has a negative meniscus shape with its convex surface facing the magnification side. The third lens element L3 has a negative meniscus shape with its convex surface facing the magnification side. The fourth lens element L4 has a biconcave shape. The fifth lens element L5 has a biconvex shape. The sixth lens element L6 has a positive meniscus shape with its convex surface facing the reduction side. The seventh lens element L7 has a positive meniscus shape with its convex surface facing the reduction side. The eighth lens element L8 has a biconcave shape. The ninth lens element L9 has a biconvex shape. The tenth lens element L10 has a biconvex shape.

[0037] The rear group Opr of the magnifying optical system Op consists of the 11th lens element L11 to the 14th lens element L14, in order from the magnification side to the reduction side. The 11th lens element L11 has a biconvex shape. The 12th lens element L12 has a positive meniscus shape with its convex surface facing the magnification side. The 13th lens element L13 has a positive meniscus shape with its convex surface facing the magnification side. The 14th lens element L14 has a negative meniscus shape with its convex surface facing the magnification side.

[0038] The relay optical system Ol is composed of lens elements L15 to L27 in order from the magnification side to the reduction side. Lens element L15 has a positive meniscus shape with its convex surface facing the reduction side. Lens element L16 has a biconcave shape. Lens element L17 has a positive meniscus shape with its convex surface facing the reduction side. Lens element L18 has a biconvex shape. Lens element L19 has a negative meniscus shape with its convex surface facing the reduction side. Lens element L20 has a biconvex shape. Lens element L21 has a positive meniscus shape with its convex surface facing the magnification side. Lens element L22 has a negative meniscus shape with its convex surface facing the magnification side. Lens element L23 has a biconcave shape. Lens element L24 has a biconvex shape. Lens element L25 has a biconvex shape. The 26th lens element L26 has a negative meniscus shape with its convex surface facing the magnification side. The 27th lens element L27 has a biconvex shape.

[0039] The relay optical system Ol consists of, in order from the magnification side to the reduction side, a first lens group G1 (L15) with positive power, a second lens group G2 (L16) with negative power, a third lens group G3 (L17) with positive power, a fourth lens group G4 (L18~L20) with positive power, a fifth lens group G5 (L21~L22) with negative power, and a sixth lens group G6 (L23~L27) with positive power. During zooming, the magnification optical system Op and the sixth lens group G6 are fixed relative to the reduction conjugate point. The first to fifth lens groups G1 to G5 may be displaced independently along the optical axis, or at least one of the first to fifth lens groups G1 to G5 may be fixed relative to the reduction conjugate point.

[0040] An intermediate imaging position MI is located between the 14th lens element L14 and the 15th lens element L15. Furthermore, aperture A is positioned between the 21st lens element L21 and the 22nd lens element L22. On the reduction side of the relay optical system Ol, an optical element P with zero optical power is positioned.

[0041] Furthermore, the zoom lens systems according to Examples 1 to 5 may include not only lens elements having optical power, but also elements with zero or substantially zero optical power, such as mirrors, diaphragms, masks, cover glass, filters, prisms, waveplates, polarizing elements, and other optical elements.

[0042] Next, the conditions that the zoom lens system according to this embodiment can satisfy will be explained. Note that multiple conditions are defined for the zoom lens system according to each embodiment, and the system may satisfy all of these conditions, or the corresponding effects may be obtained by satisfying individual conditions.

[0043] The zoom lens systems according to Examples 1 to 5 are optical systems that have an intermediate imaging position inside which is conjugate to the magnification conjugate point on the magnification side and the reduction conjugate point on the reduction side, respectively. A magnification optical system having multiple lens elements and located on the magnification side from the intermediate imaging position, The system comprises a relay optical system having multiple lens elements and located on the reduction side from the intermediate imaging position, The magnifying optical system is fixed with respect to the reduced conjugate point during zooming. The relay optical system includes a plurality of movable lens groups that can move independently in the optical axis direction during zooming. The group of movable lenses located at the most reduced position among the aforementioned multiple movable lens groups has a negative refractive power. As an example, in Examples 1 to 5, during zooming, the second lens group G2 to the fifth lens group G5 can move independently in the optical axis direction, and the fifth lens group G5 has negative refractive power.

[0044] This configuration allows for a wider-angle lens while keeping the effective diameter of the lens small. As a result, the optical system becomes lighter, and the mechanical components can also be made lighter. Furthermore, since zooming can be performed without moving the magnifying optical system, which tends to be large and heavy, the zoom mechanism can be made smaller and lighter. Furthermore, by configuring the most retracted moving lens group among the multiple moving lens groups to have negative refractive power, the amount of movement during zooming can be reduced, and the effective diameter of the lens can also be reduced, thus enabling miniaturization. In addition, field curvature and astigmatism caused by the intermediate imaging configuration can be corrected by the moving lens group with negative refractive power, thereby achieving high performance.

[0045] Furthermore, in the zoom lens systems according to Examples 1 to 5, the lens group that moves to the smallest reduction side may move to the reduction side when zooming from the wide-angle end to the telephoto end. As an example, in Examples 1-5, when zooming from the wide-angle end to the telephoto end, the fifth lens group G5 moves to the shrinking side.

[0046] This configuration allows for reduced aberration fluctuations during zooming, resulting in excellent performance across the entire zoom range.

[0047] Furthermore, the zoom lens systems according to Examples 1 to 5 may satisfy the following condition (1). 0.01 <CTN / Ymax<1.0 …(1) Here, CTN: The amount of movement of the least retracted side moving lens group during zooming. Ymax: Effective image circle diameter on the reduced side That is the case.

[0048] Condition (1) is a conditional expression that defines the relationship between the amount of movement of the least-reduced movable lens group and the effective image circle diameter at the reduced side. By satisfying condition (1), a wide-angle yet compact lens system can be realized. If the value falls below the lower limit of condition (1), the amount of movement of the least-reduced movable lens group becomes too small, making it difficult to correct field curvature and astigmatism. If the value exceeds the upper limit of condition (1), the amount of movement of the least-reduced movable lens group becomes large, increasing the overall length of the lens and making miniaturization difficult.

[0049] Furthermore, by satisfying the following condition (1A) in addition to condition (1), a more advantageous effect can be obtained. 0.02 <CTN / Ymax<0.90 …(1A)

[0050] Furthermore, in the zoom lens systems according to Examples 1 to 5, the relay optical system includes a group of fixed lenses that are fixed to the conjugate point of reduction during zooming and are located on the most reduced side, and the group of fixed lenses on the most reduced side may have a positive refractive power. As an example, in Examples 1 to 5, the sixth lens group G6, which has a positive refractive power, may be fixed relative to the reduced conjugate point during zooming.

[0051] With this configuration, the fixed lens group at the smallest zoom level has a positive refractive power, which allows for maintaining telecentricity while reducing aberration fluctuations during zooming.

[0052] Furthermore, in the zoom lens systems according to Examples 1 to 5, the relay optical system may include a group of fixed lenses that are fixed to the reduction conjugate point during zooming and are located on the most magnified side. As an example, in Examples 1 to 5, the first lens group G1 may be fixed relative to the reduction conjugate point during zooming.

[0053] This configuration reduces aberration fluctuations that occur during zooming. Furthermore, it simplifies the mechanical design of the zoom lens system.

[0054] Furthermore, in the zoom lens systems according to Examples 1 to 5, the plurality of movable lens groups may include at least four movable lens groups that move between the fixed lens group on the smallest zoom side and the fixed lens group on the largest zoom side when zooming from the wide-angle end to the telephoto end. As an example, in Examples 1 to 5, when zooming from the wide-angle end to the telephoto end, the second lens group G2 to the fifth lens group G5 may move between the sixth lens group G6 and the first lens group G1.

[0055] This configuration increases the number of variator lens groups that contribute to the overall focal length variation of the zoom lens system, thus reducing the amount of movement of each moving lens group. Consequently, aberration variations that occur during zooming are also reduced, and the amount of movement of the compensator lens group that moves to correct aberration variations is also reduced, enabling a smaller zoom lens system. Furthermore, aberration variations that occur during zooming can be corrected well, resulting in improved performance.

[0056] Furthermore, in the zoom lens systems according to Examples 1 to 5, the magnifying optical system includes a first focus lens group that can move along the optical axis during focusing. The relay optical system may include a second group of focusing lenses that can move along the optical axis during focusing.

[0057] This configuration reduces the amount of field curvature aberration during focusing, resulting in better image quality. Furthermore, because the positioning mechanisms for each focusing lens group are distributed, the center of gravity of the lens barrel can be shifted towards the smaller side.

[0058] Furthermore, the zoom lens systems according to Examples 1 to 5 may also satisfy the following condition (2). 10 <fN / fw<5000 …(2) Here, fN: Focal length of the retracted side moving lens group fw: Total focal length at the wide-angle end That is the case.

[0059] Condition (2) is a conditional expression for defining the relationship between the focal length of the smallest-reduced moving lens group and the focal point of the entire system at the wide-angle end. By satisfying condition (2), a lens system with a small lens diameter can be realized despite being wide-angle. If the value falls below the lower limit of condition (2), the effective diameter of the smallest-reduced moving lens group increases, making it heavier. If the value exceeds the upper limit of condition (2), the power of the smallest-reduced moving lens group becomes too weak, making it impossible to properly correct field curvature.

[0060] Furthermore, by satisfying the following condition (2A) in addition to condition (2), a more advantageous effect can be obtained. 100 <fN / fw<4500 …(2A)

[0061] Furthermore, the zoom lens systems according to Examples 1 to 5 may also satisfy the following condition (3). 3.0 <Ymax·f2 / fw 2 <16.0 …(3) Here, f2: Focal length of the magnifying optical system fw: Total focal length at the wide-angle end That is the case.

[0062] Condition (3) is a conditional equation that defines the relationship between the effective image circle diameter at the reduction side, the focal length of the magnifying optical system, and the overall focal length of the system at the wide-angle end. By satisfying condition (3), miniaturization and high performance can be achieved. If the values ​​fall below the lower limit of condition (3), the effective image circle diameter relative to the overall focal length becomes too small, and the power of the magnifying optical system relative to the overall focal length becomes too strong, resulting in a poor balance in correcting spherical aberration and astigmatism together with the magnifying optical system, making it difficult to achieve high performance. If the values ​​exceed the upper limit of condition (3), the effective image circle diameter relative to the overall focal length becomes too large, and the power of the magnifying optical system relative to the overall focal length becomes too weak, making it difficult to miniaturize the entire optical system.

[0063] Furthermore, by satisfying the following condition (3A) in addition to condition (3), a more advantageous effect can be obtained. 4.0 <Ymax·f2 / fw 2 <15.0 …(3A)

[0064] Furthermore, the zoom lens systems according to Examples 1 to 5 may also satisfy the following condition (4). 0.02 <enP / TL1<0.35 …(4) Here, enP: Distance along the optical axis from the most magnified side of the magnifying optical system to the entrance pupil position, with the magnified side being the incident side. TL1: Distance along the optical axis from the most reduced side to the most enlarged side of the magnifying optical system. That is the case.

[0065] Condition (4) is a conditional expression for defining the ratio of the distance on the optical axis from the most magnified side of the magnifying optical system to the entrance pupil position when the magnified side is the incident side, to the total length of the lens of the magnifying optical system. In a normal optical system that does not form an intermediate image, it is necessary to secure a long back focus. In contrast, in this embodiment, an intermediate image is formed once, and a long back focus is secured by the relay optical system. This makes it possible to move the entrance pupil position further towards the magnified side compared to a normal optical system, and it is possible to achieve a wide angle while reducing the diameter of the lens on the most magnified side of the magnifying optical system. If the value falls below the lower limit of condition (4), the total length of the lens of the magnifying optical system increases, and the diameter of the lens on the most magnified side increases. If the value exceeds the upper limit of condition (4), the entrance pupil position moves closer to the reduced side, making it difficult to secure the desired angle of view.

[0066] Furthermore, by satisfying the following condition (4A) in addition to condition (4), a more advantageous effect can be obtained. 0.05 <enP / TL1<0.30 …(4A)

[0067] Furthermore, the zoom lens systems according to Examples 1 to 5 may also satisfy the following condition (5). 2.0 <fN1 / fw<25.0 …(5) Here, fN1: The focal length of the negative lens element located on the magnifying side among the multiple lens elements that make up the least retractable moving lens group. fw: Total focal length at the wide-angle end That is the case.

[0068] Condition (5) is a conditional expression for defining the relationship between the focal length of the negative lens element located on the widest side among the multiple lens elements constituting the least-reduced moving lens group and the focal length of the entire system at the wide-angle end. By satisfying condition (5), the refractive power of the negative lens element can be secured, which is advantageous for correcting astigmatism and contributes to reducing the number of lenses constituting the least-reduced moving lens group. If the value falls below the lower limit of condition (5), the refractive power of the negative lens element becomes too strong, resulting in overcorrection. As a result, the number of positive lenses positioned on the reduced side of this negative lens element increases. If the value exceeds the upper limit of condition (5), the refractive power of the negative lens element cannot be secured, and the correction of astigmatism becomes insufficient.

[0069] Furthermore, by satisfying the following condition (5A) in addition to condition (5), a more advantageous effect can be obtained. 3.0 <fN1 / fw<24.0 …(5A)

[0070] Furthermore, the zoom lens systems according to Examples 1 to 5 may also satisfy the following condition (6). -27.0 <fP1 / fw<-4.0 …(6) Here, fP1: The focal length of the positive lens element located on the magnifying side among the multiple lens elements that make up the least retractable moving lens group. fw: Total focal length at the wide-angle end That is the case.

[0071] Condition (6) is a conditional expression for defining the relationship between the focal length of the positive lens element located on the widest side among the multiple lens elements constituting the least-reduced moving lens group and the focal length of the entire system at the wide-angle end. By satisfying condition (6), the refractive power of the positive lens element can be secured, which is advantageous for correcting astigmatism and can contribute to reducing the number of lenses constituting the least-reduced moving lens group. If the value falls below the lower limit of condition (6), the refractive power of the positive lens element becomes too strong, resulting in overcorrection. As a result, the number of negative lenses placed on the reduced side of this positive lens element increases. If the value exceeds the upper limit of condition (6), the refractive power of the positive lens element cannot be secured, and the correction of astigmatism becomes insufficient.

[0072] Furthermore, by satisfying the following condition (6A) in addition to condition (6), a more advantageous effect can be obtained. -26.0 <fP1 / fw<-5.0 …(6A)

[0073] As described above, several embodiments have been explained as examples of the technology disclosed in this application. However, the technology in this disclosure is not limited thereto and can be applied to embodiments that are modified, replaced, added, or omitted as appropriate.

[0074] The following describes numerical examples of zoom lens systems relating to Examples 1 to 5. In each numerical example, the unit of length in the table is "mm", and the unit of angle of view is "°". In each numerical example, r is the radius of curvature, d is the interplanar spacing, nd is the refractive index with respect to line d, and vd is the Abbe number with respect to line d. In each numerical example, surfaces marked with an asterisk (*) are aspherical surfaces, and the aspherical shape is defined by the following formula.

[0075]

number

[0076] (Numerical Example 1) For the zoom lens system of Numerical Example 1 (corresponding to Example 1), surface data is shown in Table 1, various data is shown in Table 2, focus data is shown in Table 3, and single lens data is shown in Table 4 (units are mm).

[0077] [Table 1] Surface data Face number rd nd vd Material 1100 1* 119.52640 9.95790 1.50940 56.5 2* 35.26070 22.38460 3 80.77750 3.54460 1.72916 54.7 4 36.63530 9.48700 5 62.52070 2.50000 1.83480 42.7 6 27.67310 21.99700 7 -70.15910 8.21900 1.80420 46.5 8 594.69480 1.33940 9 124.64020 5.54800 1.80420 46.5 10 -72.62130 12.49590 11* -26.31610 9.31280 1.51633 64.1 12* -19.60190 0.20000 13 -98.60780 7.09890 1.49700 81.6 14 -26.03630 1.62820 15 -30.52300 2.50000 1.86966 20.0 16 462.48500 1.18290 17 -1029.08340 11.21670 1.49700 81.6 18 -32.78000 5.06020 19 97.10520 10.58070 1.49700 81.6 20 -116.90860 0.20000 21 1514.53830 2.50000 1.69895 30.0 22 112.81290 44.43170 23 182.05880 11.70470 1.92286 20.9 24 -210.37220 0.20000 25 48.61070 8.96200 1.92286 20.9 26 62.66610 0.20000 27 45.19540 9.36130 1.92286 20.9 28 56.62650 8.71460 29 231.84200 3.49290 1.80420 46.5 30 53.15190 31.13120 31 -42.19710 11.00000 1.92286 20.9 32 -44.81820 Variable 33 -66.03250 10.98810 1.73800 32.3 34 105.97070 Variable 35 -195.89250 9.96520 1.86966 20.0 36 -51.81730 Variable 37 787.21310 15.00000 1.59282 68.6 38 -62.23670 4.30150 39 -64.03190 2.00000 1.59270 35.3 40 -221.32210 0.20000 41 170.84870 4.64260 1.49700 81.6 42 -170.84870 Variable 43 39.46460 5.47980 1.59270 35.3 44 100.39760 3.09940 45 (aperture) ∞ 5.22890 46 79.89460 1.50000 1.51633 64.1 47 29.25490 Variable 48 -47.20730 1.50000 1.73800 32.3 49 75.86060 2.98340 50 261.00240 5.81550 1.43700 95.1 51 -50.05640 1.00000 52 70.71160 8.65750 1.49700 81.6 53 -91.07290 7.74240 54 54.14990 2.50000 1.67300 38.3 55 39.07210 3.06530 56 44.60940 20.61510 1.43700 95.1 57 -65.26060 15.56000 58 ∞ 41.77900 1.51680 64.2 59 ∞ BF Image plane ∞ Aspherical data Front page K= 0.00000E+00, A3= 3.39820E-05, A4=-1.51102E-07, A5=-4.58997E-08 A6= 1.59795E-09, A7=-1.70289E-11, A8=-4.83390E-14, A9= 2.30699E-15 A10 = -1.29896E-17 2nd side K=-7.96856E-01, A3= 7.17508E-05, A4=-4.26012E-06, A5= 3.28783E-09 A6= 8.82707E-11, A7=-4.41750E-14, A8= 3.60550E-14, A9= 3.79852E-16 A10 = -1.13853E-17 Page 11 K= 0.00000E+00, A3= 0.00000E+00, A4=-2.02960E-05, A5= 0.00000E+00 A6=-3.69442E-08, A7= 0.00000E+00, A8=-1.54744E-10, A9= 0.00000E+00 A10 = -9.62371E-13 Side 12 K= 0.00000E+00, A3= 0.00000E+00, A4= 4.14867E-06, A5= 0.00000E+00 A6= 6.06723E-09, A7= 0.00000E+00, A8=-2.46057E-12, A9= 0.00000E+00 A10 = 0.00000E+00

[0078] [Table 2] Various data Zoom ratio 1.06933 Wide-angle, Medium, Telephoto Focal length -7.2198 -7.4490 -7.7203 F-number -2.02590 -2.00781 -1.98875 Field of view -66.9980 -66.3120 -65.5018 Image height 17.2650 17.2650 17.2650 Lens length: 566.0109, 566.0160, 566.0230 BF 1.01142 1.01655 1.02348 d32 5.4491 4.6995 3.7601 d34 9.3254 9.6493 10.0398 d36 76.8535 74.2970 71.5047 d42 2.0076 6.2752 10.9585 d47 19.5880 18.3026 16.9605 Entrance pupil position 41.6882 41.7026 41.7217 Exit pupil position -1054.2466 -786.0529 -618.7915 Front principal point position 34.4190 34.1831 33.9052 Back principal point position 573.1850 573.4164 573.6911

[0079] [Table 3] Focus data Wide-angle Telephoto Object distance 710 762 d22 45.1039 44.9532 d30 32.6985 32.3698 d32 3.2095 2.0000 Object distance 2842 3048 d22 43.5563 43.6180 d30 29.1661 29.1908 d32 8.2896 6.5141

[0080] [Table 4] Single lens data Lens starting plane, focal length 1 1 -102.2638 2 3 -95.1642 3 5 -61.4805 4 7 -77.6073 5 9 57.7824 6 11 101.0651 7 13 68.9431 8 15 -32.8471 9 17 67.8725 10 19 108.5127 11 21 -174.5214 12 23 107.2908 13 25 179.8190 14 27 174.1513 15 29 -86.5064 16 31 770.9116 17 33 -53.6694 18 35 78.4874 19 37 97.9353 20 39 -152.7368 21 41 172.6598 22 43 106.1564 23 46 -90.3026 24 48 -39.2268 25 50 96.6619 26 52 81.5406 27 54 -223.4034 28 56 64.3031

[0081] (Numerical Example 2) For the zoom lens system of Numerical Example 2 (corresponding to Example 2), surface data is shown in Table 5, various data in Table 6, focus data in Table 7, and single lens data in Table 8 (units are mm).

[0082] [Table 5] Surface data Face number rd nd vd object surface ∞ 1* 108.57490 9.86090 1.50940 56.5 2* 34.69390 20.30690 3 70.39560 3.50000 1.72916 54.7 4 38.31030 11.49800 5 77.82800 2.55000 1.83480 42.7 6 27.71270 17.45220 7 -96.08890 14.26620 1.80420 46.5 8 599.95490 1.50490 9 177.60990 4.95400 1.80420 46.5 10 -97.56240 16.45290 11* -26.06720 10.00000 1.51623 64.0 12* -19.77710 0.50000 13 -173.26010 8.24160 1.49700 81.6 14 -25.51300 1.54570 15 -29.60210 2.50000 1.86966 20.0 16 293.57420 0.52810 17 279.39620 12.50000 1.49700 81.6 18 -34.34210 0.20000 19 198.85500 4.73030 1.49700 81.6 20 -349.39300 53.33020 21 179.39700 11.00000 1.92286 20.9 22 -211.73330 0.20000 23 46.44700 8.12660 1.92286 20.9 24 60.48990 0.20000 25 41.56800 7.73270 1.92286 20.9 26 53.12620 8.05590 27 207.23960 2.65000 1.80420 46.5 28 49.42710 30.55280 29 -41.36010 11.00000 1.92286 20.9 30 -44.00000 Variable 31 -71.99170 11.00000 1.73800 32.3 32 101.16590 Variable 33 -147.84390 9.32680 1.86966 20.0 34 -50.31900 Variable 35 404.68540 15.00000 1.59282 68.6 36 -67.50700 6.02000 37 -69.53260 2.00000 1.59270 35.3 38 -346.15300 0.20000 39 163.62110 5.05600 1.49700 81.6 40 -163.62110 Variable 41 41.34420 5.16410 1.59270 35.3 42 88.81710 4.33650 43 (aperture) ∞ 8.00930 44 63.11000 1.50000 1.51633 64.1 45 28.89910 Variable 46 -47.00530 1.50000 1.73800 32.3 47 73.83990 3.01040 48 262.71120 5.84800 1.43700 95.1 49 -48.24770 1.00000 50 67.92220 8.30000 1.49700 81.6 51 -98.52820 9.50160 52 55.63230 2.50000 1.67300 38.3 53 39.87300 3.18750 54 46.17920 18.61040 1.43700 95.1 55 -63.10060 7.96480 56 ∞ 39.32900 1.51680 64.2 57 ∞ 4.59520 58 ∞ 0.55000 1.51680 64.2 59 ∞ 4.00000 60 ∞ 1.90000 1.51680 64.2 61 ∞ BF Image plane ∞ Aspheric surface Page 1 K= 0.00000E+00, A3= 3.47339E-05, A4=-6.74283E-07, A5=-3.45951E-08 A6= 1.51025E-09, A7=-1.70058E-11, A8=-4.88886E-14, A9= 2.32790E-15 A10 = -1.29625E-17 Page 2 K=-8.14220E-01, A3= 7.29749E-05, A4=-4.65798E-06, A5= 9.07093E-09 A6= 1.38885E-10, A7= 6.41794E-13, A8= 4.24196E-15, A9= 3.10765E-16 A10 = -7.64882E-18 Page 11 K= 0.00000E+00, A3= 0.00000E+00, A4=-1.89513E-05, A5= 0.00000E+00 A6=-3.99376E-08, A7= 0.00000E+00, A8=-9.35343E-11, A9= 0.00000E+00 A10 = -1.63883E-12 Page 12 K= 0.00000E+00, A3= 0.00000E+00, A4= 3.93978E-06, A5= 0.00000E+00 A6= 4.49592E-09, A7= 0.00000E+00, A8= 1.93270E-11, A9= 0.00000E+00 A10 = 0.00000E+00

[0083] [Table 6] Various データ ズームratio 1.06914 View from the middle of Kok Kok Focal distance: -7.2248 -7.4532 -7.7243 F-number -1.99360 -1.97285 -1.95415 Field of view -66.9370 -66.2428 -65.4271 Image height 17.2650 17.2650 17.2650 Lens length: 566.0144 566.0211 566.0304 BF 0.01470 0.02136 0.03046 d30 5.0844 4.4044 3.5601 d32 11.7317 12.0947 12.5117 d34 74.6222 71.8659 68.8635 d40 2.0995 6.5681 11.2409 d45 17.1124 15.7171 14.4742 Entrance pupil position 42.4243 42.4414 42.4616 Exit pupil position -1175.4441 -835.9941 -662.5318 Front principal point position 35.1551 34.9217 34.6472 Back principal point position 573.1935 573.4256 573.7024

[0084] [Table 7] Focus data Wide-angle Telephoto Object distance 710 762 d20 53.9423 53.8172 d28 31.9015 31.6260 d30 3.1236 2.0000 Object distance 2842 3048 d20 52.5571 52.5382 d28 28.8490 28.8074 d30 7.5613 6.0976

[0085] [Table 8] Single lens data Lens starting plane, focal length 1 1 -104.8116 2 3 -120.8324 3 5 -52.7756 4 7 -102.0570 5 9 78.9371 6 11 103.0090 7 13 59.1041 8 15 -30.8099 9 17 62.3604 10 19 255.7204 11 21 106.6716 12 23 169.6700 13 25 156.7144 14 27 -81.3198 15 29 747.1094 16 31 -55.4956 17 33 83.9783 18 35 98.7613 19 37 -147.1997 20 39 165.4584 21 41 125.4283 22 44 -104.8150 23 46 -38.7141 24 48 93.8125 25 50 82.2590 26 52 -223.4047 27 54 64.3506

[0086] (Numerical Example 3) For the zoom lens system of Numerical Example 3 (corresponding to Example 3), surface data is shown in Table 9, various data is shown in Table 10, focus data is shown in Table 11, and single lens data is shown in Table 12 (units are mm).

[0087] [Table 9] Surface data Face number rd nd vd object surface ∞ 1* 107.93940 9.71900 1.50940 56.5 2* 34.65080 22.17080 3 70.54480 3.50000 1.72916 54.7 4 36.30430 9.83390 5 64.40750 2.55000 1.83480 42.7 6 26.01010 18.65060 7 -103.03750 15.00000 1.80420 46.5 8 600.63130 1.75360 9 191.47870 8.08310 1.80420 46.5 10 -92.44130 10.25440 11* -26.41320 9.63150 1.51623 64.0 12* -20.25630 0.50000 13 -332.05910 8.32290 1.49700 81.6 14 -26.17580 1.53410 15 -30.65370 2.50000 1.86966 20.0 16 156.28270 0.59640 17 166.12560 12.50000 1.49700 81.6 18 -37.78170 0.51590 19 -289.27290 5.09840 1.49700 81.6 20 -77.19990 52.02180 21 176.86570 11.75190 1.92286 20.9 22 -176.73490 0.20000 23 45.86640 6.96520 1.92286 20.9 24 54.59270 0.20000 25 39.85740 8.12970 1.92286 20.9 26 49.79640 8.83050 27 196.86620 2.65000 1.80420 46.5 28 49.83570 30.13510 29 -41.15780 11.00000 1.92286 20.9 30 -44.00010 Variable 31 -70.24890 11.00000 1.73800 32.3 32 101.97770 Variable 33 -164.30960 9.63540 1.86966 20.0 34 -51.20660 Variable 35 470.56580 15.00000 1.59282 68.6 36 -66.16520 6.05460 37 -66.75820 2.00000 1.59270 35.3 38 -284.20420 0.88270 39 163.19380 4.94440 1.49700 81.6 40 -163.19380 Variable 41 42.57330 5.13850 1.59270 35.3 42 96.61330 4.30520 43 (aperture) ∞ 7.96890 44 73.76860 1.50000 1.51633 64.1 45 30.53830 Variable 46 -50.64390 1.61950 1.73800 32.3 47 66.54560 3.00290 48 198.12540 5.77670 1.43700 95.1 49 -52.21790 1.00000 50 61.19620 8.62750 1.49700 81.6 51 -107.84400 7.97930 52 53.01580 2.50000 1.67300 38.3 53 37.67940 3.33170 54 44.26600 18.60070 1.43700 95.1 55 -64.76840 7.78060 56 ∞ 39.32900 1.51680 64.2 57 ∞ 4.59520 58 ∞ 0.55000 1.51680 64.2 59 ∞ 4.00000 60 ∞ 1.90000 1.51680 64.2 61 ∞ BF Image plane ∞ Aspheric surface Page 1 K= 0.00000E+00, A3= 3.56263E-05, A4=-6.70122E-07, A5=-3.52652E-08 A6= 1.52095E-09, A7=-1.70058E-11, A8=-4.88886E-14, A9= 2.31926E-15 A10 = -1.29625E-17 Page 2 K=-8.13160E-01, A3= 7.26090E-05, A4=-4.66900E-06, A5= 9.07850E-09 A6= 1.40082E-10, A7= 6.57697E-13, A8= 4.33351E-15, A9= 3.07920E-16 A10 = -7.76577E-18 Page 11 K= 0.00000E+00, A3= 0.00000E+00, A4=-1.74363E-05, A5= 0.00000E+00 A6=-3.14611E-08, A7= 0.00000E+00, A8=-1.57381E-10, A9= 0.00000E+00 A10 = -9.46957E-13 Page 12 K= 0.00000E+00, A3= 0.00000E+00, A4= 3.32932E-06, A5= 0.00000E+00 A6= 4.08635E-09, A7= 0.00000E+00, A8= 5.86116E-12, A9= 0.00000E+00 A10 = 0.00000E+00

[0088] [Table 10] Various data Zoom ratio 1.06951 Wide-angle, Medium, Telephoto Focal length -7.2236 -7.4534 -7.7257 F-number -1.90135 -1.90180 -1.90205 Field of view -66.9335 -66.2462 -65.4362 Image height 17.2650 17.2650 17.2650 Lens length: 566.0121, 566.0180, 566.0260 BF 0.01256 0.01845 0.02641 d30 5.1448 4.4529 3.5909 d32 11.8357 12.1416 12.5089 d34 76.1761 73.5020 70.5797 d40 2.1869 6.5524 11.2141 d45 17.0344 15.7291 14.4844 Entrance pupil position 42.1904 42.2072 42.2279 Exit pupil position -864.5124 -674.6644 -556.1917 Front principal point position 34.9065 34.6714 34.3948 Back principal point position 573.1900 573.4229 573.6995

[0089] [Table 11] Focus data Wide-angle Telephoto Object distance 710 762 d20 52.6205 52.5019 d28 31.5202 31.2460 d30 3.1611 2.0000 Object distance 2842 3048 d20 51.2801 51.2468 d28 28.4192 28.3420 d30 7.6025 6.1591

[0090] [Table 12] Single lens data Lens starting plane, focal length 1 1 -104.8781 2 3 -107.2001 3 5 -53.8912 4 7 -108.3340 5 9 78.5189 6 11 109.8358 7 13 56.6631 8 15 -29.2857 9 17 63.2210 10 19 210.1999 11 21 97.3420 12 23 224.8099 13 25 155.3855 14 27 -83.6458 15 29 805.2018 16 31 -54.8740 17 33 82.2785 18 35 98.8800 19 37 -147.7192 20 39 165.0097 21 41 124.0284 22 44 -102.1322 23 46 -38.7401 24 48 95.2356 25 50 79.9095 26 52 -207.1220 27 54 63.4635

[0091] (Numerical Example 4) For the zoom lens system of Numerical Example 4 (corresponding to Example 4), surface data is shown in Table 13, various data is shown in Table 14, focus data is shown in Table 15, and single lens data is shown in Table 16 (units are mm).

[0092] [Table 13] Surface data Face number rd nd vd object surface ∞ 1* 107.68690 9.72840 1.50940 56.5 2* 34.63220 22.56300 3 70.87530 3.50000 1.72916 54.7 4 35.90850 9.42430 5 61.51430 2.55000 1.83480 42.7 6 25.61190 19.05470 7 -100.01630 15.00000 1.80420 46.5 8 596.76870 1.75850 9 183.25580 8.80660 1.80420 46.5 10 -87.61240 9.17330 11* -26.00980 9.43520 1.51623 64.0 12* -19.95640 0.50000 13 -313.22350 8.27000 1.49700 81.6 14 -26.11540 1.54520 15 -30.50610 2.50000 1.86966 20.0 16 147.36870 0.60560 17 158.01220 12.50000 1.49700 81.6 18 -38.42840 1.45500 19 -239.39850 5.30350 1.49700 81.6 20 -71.67790 50.79710 21 179.86360 11.90430 1.92286 20.9 22 -171.06680 0.20000 23 46.19840 6.73480 1.92286 20.9 24 54.51280 0.20000 25 39.42810 8.23100 1.92286 20.9 26 49.08880 9.05080 27 202.31160 2.65000 1.80420 46.5 28 50.13730 29.90550 29 -41.18220 11.00000 1.92286 20.9 30 -43.99980 Variable 31 -70.59810 11.00000 1.73800 32.3 32 102.80640 Variable 33 -166.30630 9.68500 1.86966 20.0 34 -51.33890 Variable 35 536.30660 15.00000 1.59282 68.6 36 -65.36960 5.98980 37 -65.39400 2.00000 1.59270 35.3 38 -258.05550 0.20000 39 162.66690 4.95550 1.49700 81.6 40 -162.66690 Variable 41 42.92380 5.13840 1.59270 35.3 42 99.34020 4.28940 43 (aperture) ∞ 7.96240 44 76.74060 1.50000 1.51633 64.1 45 30.90790 Can change 46 -51.99450 1.56220 1.73800 32.3 47 64.15710 3.01630 48 184.92230 5.77070 1.43700 95.1 49 -53.29550 1.00000 50 59.83760 9.02330 1.49700 81.6 51 -110.87170 7.34660 52 52.97550 2.50000 1.67300 38.3 53 37.47270 3.41830 54 44.44110 18.69280 1.43700 95.1 55 -63.58260 7.72480 56 ∞ 39.32900 1.51680 64.2 57 ∞ 4.59520 58 ∞ 0.55000 1.51680 64.2 59 ∞ 4.00000 60 ∞ 1.90000 1.51680 64.2 61 ∞ BF Image plane ∞ Aspheric surface Page 1 K= 0.00000E+00, A3= 3.51052E-05, A4=-6.50035E-07, A5=-3.56593E-08 A6= 1.52395E-09, A7=-1.70058E-11, A8=-4.88886E-14, A9= 2.31822E-15 A10 = -1.29625E-17 Page 2 K=-8.13070E-01, A3= 7.28199E-05, A4=-4.67421E-06, A5= 9.05250E-09 A6= 1.40447E-10, A7= 6.64689E-13, A8= 4.39462E-15, A9= 3.07470E-16 A10 = -7.80113E-18 Page 11 K= 0.00000E+00, A3= 0.00000E+00, A4=-1.78833E-05, A5= 0.00000E+00 A6=-3.25591E-08, A7= 0.00000E+00, A8=-1.60452E-10, A9= 0.00000E+00 A10 = -1.00596E-12 Side 12 K= 0.00000E+00, A3= 0.00000E+00, A4= 3.42081E-06, A5= 0.00000E+00 A6= 4.30100E-09, A7= 0.00000E+00, A8= 5.56065E-12, A9= 0.00000E+00 A10 = 0.00000E+00

[0093] [Table 14] Various data Zoom ratio 1.06970 Wide-angle, Medium, Telephoto Focal length -7.2233 -7.4539 -7.7268 F-number -1.90140 -1.90182 -1.90208 Field of view -66.9245 -66.2381 -65.4290 Image height 17.2650 17.2650 17.2650 Lens length: 566.0117, 566.0180, 566.0259 BF 0.01217 0.01841 0.02622 d30 5.1360 4.4478 3.5907 d32 11.8825 12.1640 12.5093 d34 77.2499 74.6008 71.6985 d40 2.3360 6.5824 11.1561 d45 16.8986 15.7081 14.5486 Entrance pupil position 42.1910 42.2068 42.2266 Exit pupil position -832.9840 -667.5316 -557.8821 Front principal point position 34.9050 34.6697 34.3928 Rear principal point position 573.1893 573.4232 573.7005

[0094] [Table 15] Focus data Wide angle Telephoto Object distance 710 762 d20 51.3988 51.2764 d28 31.3005 31.0169 d30 3.1394 2.0000 Object distance 2842 3048 d20 50.0521 50.0205 d28 28.1784 28.1050 d30 7.6082 6.1678

[0095] [Table 16] Single lens data Lens Starting surface Focal length 1 1 -104.9319 2 3 -104.2179 3 5 -54.3222 4 7 -105.5037 5 9 74.7898 6 11 108.5158 7 13 56.7830 8 15 -28.8733 9 17 63.5376 10 19 203.7187 11 21 96.5786 12 23 236.3368 13 25 154.0846 14 27 -83.5337 15 29 797.5899 16 31 -55.2272 17 33 82.1745 18 35 99.2085 19 37 -148.3547 20 39 164.4815 21 41 123.3406 22 44 -101.3582 23 46 -38.6943 24 48 95.3750 25 50 79.5926 26 52 -203.4666 27 54 63.1828

[0096] (Numerical Example 5) For the zoom lens system of Numerical Example 5 (corresponding to Example 5), surface data is shown in Table 17, various data in Table 18, focus data in Table 19, and single lens data in Table 20 (units are mm).

[0097] [Table 17] Surface data Face number rd nd vd object surface ∞ 1* 107.32640 9.75330 1.50940 56.5 2* 34.58550 23.06690 3 69.97420 3.50000 1.72916 54.7 4 35.39210 8.83770 5 57.65260 2.55000 1.83480 42.7 6 24.74670 19.92290 7 -95.31400 15.00000 1.80420 46.5 8 600.03660 1.76880 9 167.20170 8.80910 1.80420 46.5 10 -79.62250 7.70610 11* -25.27710 8.86040 1.51623 64.0 12* -19.44370 0.50000 13 -277.44070 8.24600 1.49700 81.6 14 -25.73980 1.59330 15 -29.69170 2.50000 1.86966 20.0 16 140.52190 0.62760 17 153.63470 12.50000 1.49700 81.6 18 -38.56630 3.16940 19 -224.30250 5.59290 1.49700 81.6 20 -69.32340 48.07180 21 179.14340 12.25130 1.92286 20.9 22 -166.72040 0.20000 23 45.77820 6.54020 1.92286 20.9 24 52.98250 0.20000 25 39.29160 8.37000 1.92286 20.9 26 48.97510 9.27850 27 216.19300 2.65000 1.80420 46.5 28 49.97070 29.69320 29 -41.21940 11.00000 1.92286 20.9 30 -44.00000 Variable 31 -71.26720 11.00000 1.73800 32.3 32 105.87870 Variable 33 -167.81610 9.77280 1.86966 20.0 34 -51.55790 Variable 35 836.00430 15.00000 1.59282 68.6 36 -63.14680 5.33560 37 -62.56920 2.00000 1.59270 35.3 38 -211.81410 0.20000 39 162.85640 4.95760 1.49700 81.6 40 -162.85640 Variable 41 43.51190 5.14970 1.59270 35.3 42 104.62450 4.23080 43 (aperture) ∞ 7.93870 44 84.96510 1.50000 1.51633 64.1 45 31.64870 Variable 46 -54.36570 1.50000 1.73800 32.3 47 61.44020 3.01920 48 168.76060 5.74410 1.43700 95.1 49 -54.77350 1.00000 50 57.79820 10.37250 1.49700 81.6 51 -117.01690 6.21800 52 53.09390 2.50000 1.67300 38.3 53 37.13360 3.53330 54 44.55600 18.79630 1.43700 95.1 55 -62.12050 7.72480 56 ∞ 39.32900 1.51680 64.2 57 ∞ 4.59520 58 ∞ 0.55000 1.51680 64.2 59 ∞ 4.00000 60 ∞ 1.90000 1.51680 64.2 61 ∞ BF Image plane ∞ Aspheric surface Page 1 K= 0.00000E+00, A3= 3.50560E-05, A4=-6.26647E-07, A5=-3.64379E-08 A6= 1.53157E-09, A7=-1.70058E-11, A8=-4.88886E-14, A9= 2.31486E-15 A10 = -1.29625E-17 Page 2 K=-8.13220E-01, A3= 7.38627E-05, A4=-4.69123E-06, A5= 8.97173E-09 A6= 1.40980E-10, A7= 6.82314E-13, A8= 4.57316E-15, A9= 3.06921E-16 A10 = -7.86124E-18 Page 11 K= 0.00000E+00, A3= 0.00000E+00, A4=-1.86266E-05, A5= 0.00000E+00 A6=-3.61032E-08, A7= 0.00000E+00, A8=-1.69497E-10, A9= 0.00000E+00 A10 = -1.12305E-12 Page 12 K= 0.00000E+00, A3= 0.00000E+00, A4= 3.39082E-06, A5= 0.00000E+00 A6= 4.78562E-09, A7= 0.00000E+00, A8= 2.25262E-13, A9= 0.00000E+00 A10 = 0.00000E+00

[0098] [Table 18] Various データ ズームratio 1.07012 View from the middle of Kok Kok Focal distance: -7.2231 -7.4551 -7.7296 F-number -1.90135 -1.90174 -1.90199 Field of view -66.8497 -66.1697 -65.3689 Image height 17.2650 17.2650 17.2650 Lens length: 566.0135, 566.0191, 566.0261 BF 0.01384 0.01943 0.02646 d30 5.1454 4.4626 3.6196 d32 11.9931 12.2230 12.5159 d34 79.0173 76.4053 73.5350 d40 2.5217 6.6430 11.0569 d45 16.6952 15.6388 14.6452 Entrance pupil position 42.1403 42.1550 42.1730 Exit pupil position -818.7031 -672.7451 -574.9864 Front principal point position 34.8534 34.6172 34.3395 Back principal point position 573.1910 573.4256 573.7034

[0099] [Table 19] Focus data Wide-angle Telephoto Object distance 710 762 d20 48.6847 48.5577 d28 31.1231 30.8269 d30 3.1026 2.0000 Object distance 2842 3048 d20 47.3093 47.2784 d28 27.9146 27.8423 d30 7.6865 6.2639

[0100] [Table 20] Single lens data Lens starting plane, focal length 1 1 -104.9241 2 3 -102.5916 3 5 -53.8354 4 7 -101.3005 5 9 68.1538 6 11 107.5759 7 13 56.4727 8 15 -27.9948 9 17 63.3968 10 19 199.4869 11 21 95.1909 12 23 254.0972 13 25 152.1946 14 27 -81.3958 15 29 786.4931 16 31 -56.2352 17 33 82.3563 18 35 99.6567 19 37 -150.5745 20 39 164.6725 21 41 121.8612 22 44 -98.6254 23 46 -38.8695 24 48 95.3723 25 50 79.4091 26 52 -195.8940 27 54 62.7347

[0101] Table 21 below shows the corresponding values ​​for each conditional expression in each numerical example.

[0102] [Table 21] TIFF0007829144000002.tif52155

[0103] Table 22 below shows the values ​​of the variables in each conditional expression (1) to (6) in each numerical example. [Table 22] TIFF0007829144000003.tif61155 CTN: The amount of movement of the least retracted moving lens group among multiple moving lens groups during zooming. Ymax: Effective image circle diameter on the reduced side fN: Focal length of the lens group with the smallest retraction side. fw: Total focal length at the wide-angle end f2: Focal length of the magnifying optical system enP: Distance along the optical axis from the most magnified side of the magnifying optical system to the entrance pupil position, with the magnified side being the incident side. TL1: Distance along the optical axis from the most reduced side to the most magnified side of the magnifying optical system. fN1: The focal length of the negative lens element located on the magnification side among the multiple lens elements that make up the smallest-reducing moving lens group. fP1: The focal length of the positive lens element located on the magnifying side among the multiple lens elements that make up the least retractable lens group.

[0104] (Embodiment 2) Embodiment 2 of this disclosure will be described below with reference to Figure 26. Figure 26 is a block diagram showing an example of an image projection device according to this disclosure. The image projection device 100 includes the optical system 1 disclosed in Embodiment 1, an image forming element 101, a light source 102, a control unit 110, and the like. The image forming element 101 is composed of liquid crystal, a DMD, etc., and generates an image to be projected onto the screen SR via the optical system 1. The light source 102 is composed of an LED (light-emitting diode), a laser, etc., and supplies light to the image forming element 101. The control unit 110 is composed of a CPU or MPU, etc., and controls the entire device and each component. The optical system 1 may be configured as an interchangeable lens that can be detachably attached to the image projection device 100. In this case, the device obtained by removing the optical system 1 from the image projection device 100 is an example of the main device.

[0105] The image projection device 100 described above, with the optical system 1 according to Embodiment 1, can achieve a wide-angle zoom function, and the device can be made smaller and lighter.

[0106] (Embodiment 3) Embodiment 3 of this disclosure will be described below with reference to Figure 27. Figure 27 is a block diagram showing an example of an imaging device according to this disclosure. The imaging device 200 includes the optical system 1 disclosed in Embodiment 1, an image sensor 201, a control unit 210, and the like. The image sensor 201 is composed of a CCD (charge-coupled device) image sensor, a CMOS image sensor, etc., and receives the optical image of an object OBJ formed by the optical system 1 and converts it into an electrical image signal. The control unit 110 is composed of a CPU or MPU, etc., and controls the entire device and each component. The optical system 1 may be configured as an interchangeable lens that can be detachably attached to the imaging device 200. In this case, the device obtained by removing the optical system 1 from the imaging device 200 is an example of the main device.

[0107] The imaging device 200 described above, with the optical system 1 according to Embodiment 1, can achieve a wide-angle zoom function, and the device can be made smaller and lighter.

[0108] As described above, embodiments have been explained as part of the technical disclosure in this disclosure. For this purpose, accompanying drawings and a detailed description have been provided.

[0109] Therefore, the components described in the attached drawings and detailed descriptions may include not only components essential for solving the problem, but also components that are not essential for solving the problem, provided that they illustrate the technology described above. For this reason, the mere presence of such non-essential components in the attached drawings or detailed descriptions should not be immediately assumed to mean that these non-essential components are essential.

[0110] Furthermore, since the embodiments described above are for illustrative purposes of the technology described herein, various modifications, substitutions, additions, omissions, etc., can be made within the scope of the claims or their equivalents. [Industrial applicability]

[0111] This disclosure is applicable to image projection devices such as projectors and head-up displays, and imaging devices such as digital still cameras, digital video cameras, surveillance cameras in surveillance systems, webcams, and in-vehicle cameras. In particular, this disclosure is applicable to optical systems that require high image quality, such as projectors, digital still camera systems, and digital video camera systems.

Claims

1. An optical system having an intermediate imaging position which is conjugate to the magnification conjugate point on the magnification side and the reduction conjugate point on the reduction side, respectively, A magnification optical system having multiple lens elements and located on the magnification side from the intermediate imaging position, The system comprises a relay optical system having multiple lens elements and located on the reduction side from the intermediate imaging position, The magnifying optical system is fixed with respect to the reduced conjugate point during zooming. The relay optical system includes a plurality of movable lens groups that can move independently in the optical axis direction during zooming. The optical system wherein the most retracted moving lens group among the plurality of moving lens groups has a negative refractive power and satisfies the following condition (3). 3.0<Ymax・f2 / fw ２ <16.0 …(3) Here, Ymax: Effective image circle diameter at the reduction side f2: Focal length of the magnifying optical system fw: Total focal length at the wide-angle end That is the case.

2. The optical system according to claim 1, wherein the lens group that moves to the smallest reduction side moves to the reduction side when zooming from the wide-angle end to the telephoto end.

3. The optical system according to claim 1, satisfying the following condition (1). 0.01<CTN / Ymax<1.0...(1) Here, CTN: The amount of movement of the least-reduced side moving lens group during zooming. That is the case.

4. The optical system according to claim 1, wherein the relay optical system includes a group of fixed lenses that are fixed with respect to the reduced conjugate point during zooming and are located on the most reduced side, and the group of fixed lenses on the most reduced side has a positive refractive power.

5. The optical system according to claim 1, wherein the relay optical system includes a group of fixed lenses that are fixed with respect to the reduced conjugate point during zooming and are located on the most magnified side.

6. The relay optical system includes a group of fixed lenses that are fixed with respect to the reduced conjugate point during zooming and are located on the most reduced side, The optical system according to claim 5, wherein the plurality of movable lens groups include at least four movable lens groups that move between the fixed lens group on the smallest zoom side and the fixed lens group on the largest zoom side when zooming from the wide-angle end to the telephoto end.

7. The magnifying optical system includes a first group of focusing lenses that can move along the optical axis during focusing, The optical system according to claim 1, wherein the relay optical system includes a second group of focusing lenses that can move along the optical axis during focusing.

8. The optical system according to claim 1, satisfying the following condition (2). 10<fN / fw<5000…(2) Here, fN: Focal length of the least retracted moving lens group fw: Total focal length at the wide-angle end That is the case.

9. The optical system according to claim 1, satisfying the following condition (4). 0.02<enP / TL1<0.35...(4) Here, enP: Distance along the optical axis from the most magnified side of the magnifying optical system to the entrance pupil position when the magnified side is considered the incident side. TL1: Distance along the optical axis from the most reduced side to the most enlarged side of the magnifying optical system. That is the case.

10. The optical system according to claim 1, satisfying the following condition (5). 2.0<fN1 / fw<25.0...(5) Here, fN1: The focal length of the negative lens element located on the magnification side among the multiple lens elements constituting the least-reduced moving lens group. fw: Total focal length at the wide-angle end That is the case.

11. The optical system according to claim 1, satisfying the following condition (6). -27.0<fP1 / fw<-4.0...(6) Here, fP1: The focal length of the positive lens element located on the magnifying side among the multiple lens elements constituting the least-reduced moving lens group. fw: Total focal length at the wide-angle end That is the case.

12. An optical system having an intermediate imaging position which is conjugate to the magnification conjugate point on the magnification side and the reduction conjugate point on the reduction side, respectively, A magnification optical system having multiple lens elements and located on the magnification side from the intermediate imaging position, The system comprises a relay optical system having multiple lens elements and located on the reduction side from the intermediate imaging position, The magnifying optical system is fixed with respect to the reduced conjugate point during zooming. The relay optical system includes a plurality of movable lens groups that can move independently in the optical axis direction during zooming. The most retractable moving lens group among the plurality of moving lens groups has a negative refractive power. The relay optical system includes a group of fixed lenses that are fixed relative to the conjugate point of reduction during zooming and are located on the most reduced side, and the group of fixed lenses on the most reduced side has a positive refractive power. The relay optical system includes a group of fixed lenses that are fixed relative to the reduced conjugate point during zooming and are located on the most magnified side.

13. An optical system having an intermediate imaging position which is conjugate to the magnification conjugate point on the magnification side and the reduction conjugate point on the reduction side, respectively, A magnification optical system having multiple lens elements and located on the magnification side from the intermediate imaging position, The system comprises a relay optical system having multiple lens elements and located on the reduction side from the intermediate imaging position, The magnifying optical system is fixed with respect to the reduced conjugate point during zooming. The relay optical system includes a plurality of movable lens groups that can move independently in the optical axis direction during zooming. The optical system wherein the most retracted moving lens group among the plurality of moving lens groups has a negative refractive power and satisfies the following condition (6). -27.0<fP1 / fw<-4.0...(6) Here, fP1: The focal length of the positive lens element located on the magnifying side among the multiple lens elements constituting the least-reduced moving lens group. fw: Total focal length at the wide-angle end That is the case.

14. An optical system according to any one of claims 1 to 13, An image projection device comprising an image forming element that generates an image to be projected onto a screen via the optical system.

15. An optical system according to any one of claims 1 to 13, An imaging device comprising: an image sensor that receives an optical image formed by the optical system and converts it into an electrical image signal.

Images