答:这个问题与物理中的几何光学知识有关。我们知道近视镜是凹透镜,远视镜为凸透镜。凹透镜能发散光线,凸透镜能会聚光线,它们均有两个焦点。凹透镜为虚焦点,通常规定它的焦距为负;凸透镜为实焦点,通常规定它的焦距为正。对于曲率不同的透镜,它们会聚或发散的本领是不同的。透镜的焦距f越短,即1/f的数值越大,它使 A: This problem is related to the knowledge of geometrical optics in physics. We know that myopia is concave lens, hyperopia lens is convex lens. Concave lenses can diffuse light, and convex lenses can condense light, both of which have two focal points. A concave lens is a virtual focal point, which usually specifies that its focal length is negative; a convex lens is a real focal point, usually defining its focal length as positive. For lenses with different curvatures, their ability to converge or diverge is different. The shorter the focal length f of the lens, ie the larger the value of 1 / f, it is