| CPC H05B 47/155 (2020.01) [F21V 5/004 (2013.01); F21V 5/006 (2013.01); F21V 5/008 (2013.01); F21V 5/045 (2013.01); G02B 9/12 (2013.01); F21Y 2105/16 (2016.08); F21Y 2115/10 (2016.08)] | 5 Claims |

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1. A variable focus flashlight module, sequentially from a magnified side to a minified side along an optical axis of the variable focus flashlight module, comprising:
a first lens, having a negative refracting power, wherein the first lens is a negative meniscus lens with a concave surface facing the magnified side;
a second lens, having a positive refracting power, wherein the second lens is a biconvex lens;
a third lens, having a positive refracting power, wherein the third lens is a biconvex lens; and
a light source module, comprising a plurality of light emitting elements arranged in an array;
wherein a total length of the variable focus flashlight module is a constant, and a ratio of a focal length of the second lens to a focal length of the third lens falls within a range of 1.78 to 3.02, both of an object-side surface and an image-side surface of the first lens, the second lens and the third lens are even aspherical surfaces.
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