PURPOSE: To control the focal length in normal and macro ranges by using two movable lens components and providing a controller which controls the focal length in the normal range and a controller which controls macro-photographing and the focal length in the macro-range.
CONSTITUTION: A lens system consists of the first fixed positive component 1, the second movable negative component 2 which changes the resultant focal length, the third movable component 3 which holds the image surface in a certain position, the fourth fixed positive component 4, and a fixed positive master lens system 5 which are arranged in order from the object side. When the third component 3 is moved to a position 3' while holding positions of the other components as they are, the lens system is focused to the object in the macro-range. When the third component 3 is moved to a position 3a and the focal length is changed additionally in the macro range, the image state is kept constant. When the second and the third components are moved to positions 2b and 3b and positions 2c and 3c, the object image on a place 6 in the macro- range is enlarged. Thus, the focal length in normal and macro-ranges is controlled.
PEETAA REBUI FUON BERUBUAARU