In this shape, the lens focuses images behind the retina.

在这种形状下，晶状体聚焦视网膜后面的图像。

The lens focuses the image in front of the retina.

晶状体会把光线聚焦到视网膜前方。

In this shape, the lens can focus up close images onto the retina.

在这种形状下，晶状体可以将近距离的图像聚焦到视网膜上。

In a healthy eye, muscles have to squeeze the lens in order to focus up close images onto the retina.

在健康的眼睛中，肌肉必须挤压晶状体才能将近距离的图像聚焦到视网膜上。

This will result in excessive and continuous use of intraocular (ciliary) muscles in order to keep the image focused on the retina, resulting in pain.

这将导致过度和持续地使用眼内（睫状肌），以保持图像聚焦在视网膜上，导致疼痛。

So nearsightedness can be corrected by diverging lenses, spreading out the light rays so a focused image is formed at the proper distance.

因此，近视可以通过发散镜片来矫正 ，分散光线，从而 在适当的距离形成聚焦图像。

But a unique thing about hyperopia is that if these patients increase the power of their lens by contraction of certain intraocular muscles, they can focus the image accurately on their retina.

但远视的一个独特之处在于，如果这些患者通过收缩某些眼内肌肉来增加晶状体的放大率，他们就可以将图像准确地聚焦到视网膜上。