| 摘要 |
The present invention relates to a telecentric optical device for varying a focal distance, which can vary focus. More specifically, the telecentric optical device comprises: a body; a fixing lens unit; a moving lens unit; a lens drive unit; a photographing unit; a rotation unit; a stopper; and a lighting unit. Therefore, even if a focal distance is changed, or the depth is left when photographing, all principal rays can be maintained in a state of being parallel with an optical axis with respect to a phase space or an object space, and a decline in a photographing image can be prevented. |
