| 摘要 |
PURPOSE:To obtain a miniature two-focus objective lens which has drastically simpli fied structure, by constituting it so that the position of each of a first lens group (front group) having a negative refracting power and a second lens group (rear group) having a positive refracting power can be adjusted independently. CONSTITUTION:At the time of adjusting a lens against an image pickup element 1, a front group 2 and a rear group 3 are set to a state of a short focal distance, and by turning an eccentric pin 34, a rear group adjusting substrate 31 is moved along an optical axis M, and by clamping a fixing screw 35 when a rear group lens has been positioned at a prescribed position, the position of the rear group lens is fixed. Subsequently, when a lens switching lever 7 is turned clockwise, a front group moving substrate 21 is energized to the rear group side through a pin 25 which is provided vertically, one end 21b thereof is brought to press-contacting with an eccentric pin 12 provided vertically on a substrate 4 and a position of the front group lens is deter mined. On the other hand, by giving a clockwise energizing force to a rear group moving lever 36, a focal distance of the lens becomes long. In such a way, by turning the eccentric pin 12 and 13 and setting the best focal position in a short focus or a long focus, a satisfactory lens system can be obtained.
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