| 摘要 |
PURPOSE:To observe an image with good resolving power by varying the magnification of an image of an object formed on the objective-side end surface of an image guide fiber. CONSTITUTION:Prior to observation, switch operation is performed to flow AC currents through electromagnets 10 and 16 of a magnification variation driving means synchronously in the reverse direction. Consequently, the electromagnets 10 and 16 attract holding rings 9 and 15 magnetically in the reverse direction. Namely, when the holding ring 15 on the side of an optical objective system 6 is attracted, the holding ring 12 on the side of an optical ocular system 12 is repulsed. Further, when the holding ring 9 is repulsed, the holding ring 15 is attracted to the contrary. In this case, the holding rings 9 and 15 have their movement ranges specified by stoppers, etc. Consequently, when the optical objective system 6 increases in magnification, the optical ocular system 12 increases in magnification accordingly to reduce an enlarged image to the original size during the observation. |
