| 摘要 |
<p>The present invention relates to a compact lens system and, more specifically, to a compact wide angle lens system adopted for a compact electronic equipment such as robot cleaners. According to the present invention, a first lens group with negative power, an f-stop, and a second lens group with positive power are arranged in order from an object side toward an imaging device where an image is formed. The first lens group with the negative power includes one first lens with negative power, one second lens with negative power, and one third lens with positive power; and the second lens group with the positive power includes one fourth lens with positive power. Assuming the combined focal distance of the first lens group as F1 and the combined focal distance of the second lens group as F2; -6.5<F1/F2<-2.5 is satisfied. The first lens and the second lens of the first lens group are formed of a glass material.</p> |
