Light supplementing device

Abstract

The utility model relates to a light supplementing device which sequentially comprises a first lens, a second lens, a third lens and a light source in the extension direction of an optical axis, the focal length of the first lens is f1, the focal length of the second lens is f2, the focal length of the third lens is f3, and the focal length of the light supplementing device is f; the number of lenses used by the light supplementing device is small, and the light supplementing device is simple in structure and easy to miniaturize. The light supplementing device provided by the utility model can effectively reduce the glare phenomenon, and improves the projection light supplementing effect.

Description

Technical Field

[0001] The utility model relates to the field of lenses, in particular to a fill light device. Background Art

[0002] Surveillance cameras are usually equipped with a fill light device, which can provide additional lighting during nighttime shooting to improve the surveillance shooting effect. Existing fill light devices use a large number of lenses and have a complex structure, which makes it difficult to reduce the size of the fill light device. In addition, existing fill light devices are prone to glare when turned on, which can easily irritate human eyes at night. Utility Model Content

[0003] Based on this, it is necessary to provide a fill light device to address the problems of large size and easy glare.

[0004] A fill light device comprises a first lens, a second lens, a third lens and a light source in sequence in the direction of extension of an optical axis, the focal length of the first lens is f1, the focal length of the second lens is f2, the focal length of the third lens is f3, and the focal length of the fill light device is f;

[0005] Satisfies: |f1|<f2|<f3|,

[0006] The effective aperture of the first lens of the utility model is Φ1, and the total optical length of the fill light device is TTL, satisfying

[0007] The utility model has a width of 17.5 mm ≤ TTL ≤ 21.6 mm, and a width of 12.6 mm ≤ f ≤ 14 mm.

[0008] The fill light device of the utility model further comprises a supporting unit, the first lens is supported on the supporting unit, and the supporting unit is attached to the edge portion of the near light surface of the first lens.

[0009] The light-filling device of the utility model further comprises an aperture, and the aperture is located between the first lens and the second lens.

[0010] The refractive index of the first lens of the utility model is V d1 , the Abbe number of the first lens is N d1 , the refractive index of the second lens is V d2 , the Abbe number of the second lens is N d2 , the refractive index of the third lens is V d3 , the Abbe number of the third lens is N d3 ;

[0011] 1.4<N d1 <1.6,30<Vd1 <70,1.4<N d2 <1.6,30<V d2 <70,1.4<N d3 <1.6,30<V d3 <70.

[0012] The utility model d1 =N d2 =N d3 , V d1 =V d2 =V d3 .

[0013] In the present invention, the curvature radii of the near light surface and the far light surface of the first lens are both positive values, the curvature radius of the far light surface of the second lens is a positive value, the curvature radius of the near light surface of the second lens is a negative value, and the curvature radii of the near light surface and the far light surface of the third lens are both negative values.

[0014] The first lens and the second lens of the utility model are both positive focal length lenses.

[0015] In the present invention, the first lens, the second lens and the third lens are all aspherical lenses.

[0016] The beneficial effects of the utility model are:

[0017] The fill-light device of the utility model uses a small number of lenses, has a simple structure, and is easy to be miniaturized. The fill-light device provided by the utility model can effectively reduce the occurrence of glare and improve the projection fill-light effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The light path diagram of the fill light device in Embodiment 1 and Embodiment 2 of the present utility model;

[0019] Figure 2 is the spot irradiance curve of the fill light device in Example 1 of the utility model;

[0020] Figure 3 This is the spot irradiance curve of the fill light device in Example 2 of the utility model.

[0021] Reference numerals:

[0022] 1. First lens; 2. Second lens; 3. Third lens; 4. Light source. DETAILED DESCRIPTION

[0023] In order to make the above-mentioned purposes, features and advantages of the utility model more obvious and easy to understand, the specific implementation methods of the utility model are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the utility model. However, the utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the utility model, so the utility model is not limited by the specific embodiments disclosed below.

[0024] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0025] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present utility model, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0026] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0027] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0028] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0029] Embodiment 1:

[0030] See also Figure 1 This embodiment provides a fill light device, which includes a first lens 1, a second lens 2, a third lens 3 and a light source 4 in sequence in the extension direction of the optical axis.

[0031] Among them, the side of the first lens 1 close to the light source 4 is the near light surface of the first lens 1, the side of the first lens 1 away from the light source 4 is the far light surface of the first lens 1, the side of the second lens 2 close to the light source 4 is the near light surface of the second lens 2, the side of the second lens 2 away from the light source 4 is the far light surface of the second lens 2, the side of the third lens 3 close to the light source 4 is the near light surface of the third lens 3, and the side of the third lens 3 away from the light source 4 is the far light surface of the third lens 3. That is, the fill light device of this embodiment has six mirror surfaces, which are, from left to right, the far light surface of the first lens 1, the near light surface of the first lens 1, the far light surface of the second lens 2, the near light surface of the second lens 2, the far light surface of the third lens 3, and the near light surface of the third lens 3.

[0032] The near light surface of the first lens 1 plays the same role as the aperture. In some embodiments, the fill light device further includes a support unit, which can support the first lens 1, and the edge of the near light surface of the first lens 1 is attached to the support unit, so that the edge of the near light surface of the first lens 1 is blocked by the support unit, and the center of the near light surface of the first lens 1 is used as the aperture. In other embodiments, the fill light device further includes an aperture, which is directly arranged between the first lens 1 and the second lens 2.

[0033] A total of six mirror surfaces, namely, the first lens 1 far light surface, the first lens 1 near light surface, the second lens 2 far light surface, the second lens 2 near light surface, the third lens 3 far light surface and the third lens 3 near light surface, can be designed as aspherical surfaces. The specific design formula is: Where Z is the distance from a point on the mirror to the center of the mirror, c is the reciprocal of the radius of curvature R at the center of the mirror, k is the cone coefficient, and A, B, C, D, E, and F are high-order aspheric coefficients.

[0034] The focal length of the first lens 1 is f1, the focal length of the second lens 2 is f2, the focal length of the third lens 3 is f3, and the focal length of the fill light device is f. The fill light device should satisfy |f1|<f2|<f3|,

[0035] Preferably, the effective aperture of the first lens 1 is Φ1, and the total optical length of the fill light device is TTL.

[0036] Preferably, the refractive index of the first lens 1 is V d1 , the Abbe number of the first lens 1 is N d1 , the refractive index of the second lens 2 is V d2 , the Abbe number of the second lens 2 is N d2 , the refractive index of the third lens 3 is V d3 , the Abbe number of the third lens 3 is N d3 , the fill light device can also meet 1.4<N d1 <1.6,30<V d1 <70,1.4<N d2 <1.6,30<V d2 <70,1.4<N d3 <1.6,30<V d3 <70.

[0037] The specific structural parameters corresponding to the fill light device of this embodiment are shown in Table 1 and Table 2. Among them, the mirror numbers 1-6 correspond to the far light surface of the first lens 1, the near light surface of the first lens 1, the far light surface of the second lens 2, the near light surface of the second lens 2, the far light surface of the third lens 3, and the near light surface of the third lens 3.

[0038] Table 1

[0039]

[0040]

[0041] Table 2

[0042] Mirror number A B C D E F 1 <![CDATA[9.61×10 -5 ]]> <![CDATA[7.75×10 -6 ]]> <![CDATA[3.79×10 -6 ]]> <![CDATA[-3.01×10 -8 ]]> <![CDATA[-2.18×10 -9 ]]> <![CDATA[-1.39×10 -10 ]]> 2 <![CDATA[-3.03×10 -6 ]]> <![CDATA[-4.54×10 -15 ]]> <![CDATA[-1.34×10 -9 ]]> <![CDATA[1.71×10 -10 ]]> <![CDATA[-2.08×10 -11 ]]> <![CDATA[-1.96×10 -17 ]]> 3 <![CDATA[9.85×10 -5 ]]> <![CDATA[8.29×10 -06 ]]> <![CDATA[-1.77×10 -15 ]]> <![CDATA[4.80×10 -8 ]]> <![CDATA[2.96×10 -9 ]]> <![CDATA[2.23×10 -10 ]]> 4 <![CDATA[-9.22×10 -13 ]]> <![CDATA[-2.20×10 -13 ]]> <![CDATA[-2.23×10 -6 ]]> <![CDATA[-2.65×10 -17 ]]> <![CDATA[-1.33×10 -17 ]]> <![CDATA[-7.0×10 -19 ]]> 5 <![CDATA[-7.20×10 -13 ]]> <![CDATA[-1.83×10 -6 ]]> <![CDATA[2.97×10 -14 ]]> <![CDATA[1.97×10 -15 ]]> <![CDATA[1.21×10 -16 ]]> <![CDATA[7.40×10 -18 ]]> 6 <![CDATA[-1.0×10 -12 ]]> <![CDATA[6.0×10 -4 ]]> <![CDATA[1.41×10 -4 ]]> <![CDATA[-1.9×10 -7 ]]> <![CDATA[-2.56×10 -17 ]]> <![CDATA[-5.32×10 -9 ]]>

[0043] Based on Table 1, it can be seen that in this embodiment Nd1 =N d2 =N d3 , V d1 =V d2 =V d3 , the first lens 1, the second lens 2 and the third lens 3 can be obtained by cutting the same piece of material. The curvature radii of the near light surface and the far light surface of the first lens 1 are both positive values, and the curvature radii of the near light surface and the far light surface of the third lens 3 are both negative values. If the radius of curvature at the center of the mirror surface is a positive value, it means that the center of curvature of the mirror surface is located on the right side of the mirror surface. Conversely, if the radius of curvature at the center of the mirror surface is a negative value, it means that the center of curvature of the mirror surface is located on the left side of the mirror surface. Taking the first lens 1 as an example, the center of curvature of the near light surface of the first lens 1 is located on the right side of the near light surface of the first lens 1, and the center of curvature of the far light surface of the first lens 1 is located on the right side of the far light surface of the first lens 1. It is worth noting that the curvature radius of the far light surface of the second lens 2 (the left side surface of the second lens 2) in this embodiment is a positive value, and the curvature radius of the near light surface of the second lens 2 (the right side surface of the second lens 2) is a negative value.

[0044] Furthermore, in this embodiment, the first lens 1, the second lens 2 and the third lens 3 are all positive power lenses, f=12.6 mm, TTL=17.5 mm,

[0045] See also Figure 2 , the angle corresponding to 50% light intensity is 2.6°, which proves that the fill light device of this embodiment can effectively reduce the occurrence of glare.

[0046] Embodiment 2:

[0047] See also Figure 1 This embodiment provides a fill light device, which includes a first lens 1, a second lens 2, a third lens 3 and a light source 4 in sequence in the extension direction of the optical axis.

[0048] Among them, the side of the first lens 1 close to the light source 4 is the near light surface of the first lens 1, the side of the first lens 1 away from the light source 4 is the far light surface of the first lens 1, the side of the second lens 2 close to the light source 4 is the near light surface of the second lens 2, the side of the second lens 2 away from the light source 4 is the far light surface of the second lens 2, the side of the third lens 3 close to the light source 4 is the near light surface of the third lens 3, and the side of the third lens 3 away from the light source 4 is the far light surface of the third lens 3. That is, the fill light device of this embodiment has six mirror surfaces, which are, from left to right, the far light surface of the first lens 1, the near light surface of the first lens 1, the far light surface of the second lens 2, the near light surface of the second lens 2, the far light surface of the third lens 3, and the near light surface of the third lens 3.

[0049] The near light surface of the first lens 1 plays the same role as the aperture. In some embodiments, the fill light device further includes a support unit, which can support the first lens 1, and the edge of the near light surface of the first lens 1 is attached to the support unit, so that the edge of the near light surface of the first lens 1 is blocked by the support unit, and the center of the near light surface of the first lens 1 is used as the aperture. In other embodiments, the fill light device further includes an aperture, which is directly arranged between the first lens 1 and the second lens 2.

[0050] A total of six mirror surfaces, namely, the first lens 1 far light surface, the first lens 1 near light surface, the second lens 2 far light surface, the second lens 2 near light surface, the third lens 3 far light surface and the third lens 3 near light surface, can be designed as aspherical surfaces. The specific design formula is: Where Z is the distance from a point on the mirror to the center of the mirror, c is the reciprocal of the radius of curvature R at the center of the mirror, k is the cone coefficient, and A, B, C, D, E, and F are high-order aspheric coefficients.

[0051] The focal length of the first lens 1 is f1, the focal length of the second lens 2 is f2, the focal length of the third lens 3 is f3, and the focal length of the fill light device is f. The fill light device should satisfy |f1|<f2|<f3|,

[0052] Preferably, the effective aperture of the first lens 1 is Φ1, and the total optical length of the fill light device is TTL, satisfying

[0053] Preferably, the refractive index of the first lens 1 is V d1 , the Abbe number of the first lens 1 is N d1 , the refractive index of the second lens 2 is V d2 , the Abbe number of the second lens 2 is N d2 , the refractive index of the third lens 3 is V d3 , the Abbe number of the third lens 3 is N d3 , the fill light device can also meet 1.4<N d1 <1.6,30<V d1 <70,1.4<N d2 <1.6,30<V d2 <70,1.4<N d3 <1.6,30<V d3 <70.

[0054] The specific structural parameters corresponding to the fill light device of this embodiment are shown in Table 3 and Table 4. Among them, the mirror numbers 1-6 correspond to the far light surface of the first lens 1, the near light surface of the first lens 1, the far light surface of the second lens 2, the near light surface of the second lens 2, the far light surface of the third lens 3 and the near light surface of the third lens 3.

[0055] Table 3

[0056]

[0057] Table 4

[0058] Mirror number A B C D E F 1 <![CDATA[4.38×10 -4 ]]> <![CDATA[1.06×10 -5 ]]> <![CDATA[3.5×10 -6 ]]> <![CDATA[-1.49×10 -8 ]]> <![CDATA[-1.24×10 -9 ]]> <![CDATA[-8.51×10 -12 ]]> 2 <![CDATA[-7.21×10 -4 ]]> <![CDATA[-3.13×10 -15 ]]> <![CDATA[1.0×10 -7 ]]> <![CDATA[-8.63×10 -8 ]]> <![CDATA[4.86×10 -9 ]]> <![CDATA[-1.48×10 -17 ]]> 3 <![CDATA[-4.39×10 -4 ]]> <![CDATA[6.63×10 -5 ]]> <![CDATA[-1.72×10 -15 ]]> <![CDATA[4.21×10 -7 ]]> <![CDATA[6.50×10 -9 ]]> <![CDATA[3.70×10 -10 ]]> 4 <![CDATA[-8.13×10 -13 ]]> <![CDATA[1.90×10 -13 ]]> <![CDATA[-2.01×10 -7 ]]> <![CDATA[-1.50×10 -17 ]]> <![CDATA[-9.88×10 -18 ]]> <![CDATA[-5.24×10 -10 ]]> 5 <![CDATA[8.31×10 -13 ]]> <![CDATA[5.39×10 -5 ]]> <![CDATA[2.58×10 -14 ]]> <![CDATA[2.52×10 -15 ]]> <![CDATA[1.41×10 -16 ]]> <![CDATA[1.07×10 -17 ]]> 6 <![CDATA[-8.79×10 -13 ]]> <![CDATA[5.24×10 -4 ]]> <![CDATA[8.63×10 -5 ]]> <![CDATA[-2.20×10 -6 ]]> <![CDATA[-2.71×10 -17 ]]> <![CDATA[-2.13×10 -8 ]]>

[0059] Furthermore, in this embodiment, the first lens 1 and the second lens 2 are both positive power lenses, the third lens 3 is a negative power lens, f=14 mm, TTL=21.6 mm,

[0060] See also Figure 3 , the angle corresponding to 50% light intensity is 3°, which proves that the fill light device of this embodiment can effectively reduce the occurrence of glare.

[0061] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0062] The above-mentioned embodiments only express several implementation methods of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the utility model patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.

Claims

1. A fill light device, characterized in that: The optical system comprises a first lens (1), a second lens (2), a third lens (3) and a light source (4) in sequence in the direction of extension of the optical axis, the focal length of the first lens (1) is f1, the focal length of the second lens (2) is f2, the focal length of the third lens (3) is f3, and the focal length of the fill light device is f; Satisfies: f1<f2<f3, 2. The fill light device according to claim 1, characterized in that: The effective aperture of the first lens (1) is Φ1, the total optical length of the fill light device is TTL, and 3. The fill light device according to claim 2, characterized in that: 17.5mm≤TTL≤21.6mm, 12.6mm≤f≤14mm.

4. The fill light device according to claim 1, characterized in that: The fill light device also includes a supporting unit, the first lens (1) is supported on the supporting unit, and the supporting unit is attached to the edge portion of the near light surface of the first lens (1).

5. The fill light device according to claim 1, characterized in that: The light-filling device further comprises an aperture, wherein the aperture is located between the first lens (1) and the second lens (2).

6. The fill light device according to claim 1, characterized in that: The refractive index of the first lens (1) is V d1 , the Abbe number of the first lens (1) is N d1 The refractive index of the second lens (2) is V d2 , the Abbe number of the second lens (2) is N d2 The refractive index of the third lens (3) is V d3 , the Abbe number of the third lens (3) is N d3 ; 1.4<N d1 <1.6,30<V d1 <70,1.4<N d2 <1.6,30<V d2 <70,1.4<N d3 <1.6,30<V d3 <70。 7. The fill light device according to claim 6, characterized in that: N d1 =N d2 =N d3 ,V d1 =V d2 =V d3 。 8. The fill light device according to claim 1, characterized in that: The curvature radii of the near light surface and the far light surface of the first lens (1) are both positive values, the curvature radius of the far light surface of the second lens (2) is a positive value, the curvature radius of the near light surface of the second lens (2) is a negative value, and the curvature radii of the near light surface and the far light surface of the third lens (3) are both negative values.

9. The fill light device according to claim 1, characterized in that: The first lens (1) and the second lens (2) are both positive power lenses.

10. The fill light device according to claim 1, characterized in that: The first lens (1), the second lens (2) and the third lens (3) are all aspherical lenses.

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