Abstract: In a zoom lens of a fixed total length, at the time of changing the magnification from the wide-angle end toward the telephoto end, the first lens group is anchored while the second lens group is moved, and the third and fourth lens groups are moved so as to be located at the object side of the telephoto end relative to the wide-angle end, such that: the interval between the second and third lens groups is decreased at the telephoto end relative to the wide-angle end; the interval between the third and fourth lens groups is increased at the telephoto end relative to the wide-angle end; and the interval between the fourth and fifth lens groups is increased at the telephoto end relative to the wide-angle end, and at the time of focusing a near object point from a remote object point, the second lens group is moved.

Abstract: A zoom lens comprises a first lens unit G1 having a positive refractive power, a second lens unit G2 having a negative refractive power, a third lens unit G3 having a positive refractive power, a fourth lens unit G4 having a negative refractive power, a fifth lens unit G5, and a sixth lens unit G6 having a positive refractive power. Zooming from a wide angle end to a telephoto end is carried out by changing a distance between the lens units, and a distance between the first lens unit G1 and the third lens unit G3 narrows at the telephoto end than at the wide angle end, and the first lens unit G1 is stationary at the time of zooming from the wide angle end to the telephoto end, and lens units from the second lens unit G2 to the fifth lens unit G5 move.

Abstract: A zoom lens comprises a first lens unit G1 having a positive refractive power, a second lens unit G2 having a negative refractive power, a third lens unit G3 having a positive refractive power, a fourth lens unit G4 having a negative refractive power, a fifth lens unit G5, and a sixth lens unit G6 having a positive refractive power. Zooming from a wide angle end to a telephoto end is carried out by changing a distance between the lens units, and a distance between the first lens unit G1 and the third lens unit G3 narrows at the telephoto end than at the wide angle end, and the first lens unit G1 is stationary at the time of zooming from the wide angle end to the telephoto end, and lens units from the second lens unit G2 to the fifth lens unit G5 move.

Abstract: A zoom lens comprises a first lens unit G1 having a positive refractive power, a second lens unit G2 having a negative refractive power, a third lens unit G3 having a positive refractive power, a fourth lens unit G4 having a negative refractive power, a fifth lens unit G5, and a sixth lens unit G6 having a positive refractive power. Zooming from a wide angle end to a telephoto end is carried out by changing a distance between the lens units, and a distance between the first lens unit G1 and the third lens unit G3 narrows at the telephoto end than at the wide angle end, and the first lens unit G1 is stationary at the time of zooming from the wide angle end to the telephoto end, and lens units from the second lens unit G2 to the fifth lens unit G5 move.

Abstract: In a zoom lens of a fixed total length, at the time of changing the magnification from the wide-angle end toward the telephoto end, the first lens group is anchored while the second lens group is moved, and the third and fourth lens groups are moved so as to be located at the object side of the telephoto end relative to the wide-angle end, such that: the interval between the second and third lens groups is decreased at the telephoto end relative to the wide-angle end; the interval between the third and fourth lens groups is increased at the telephoto end relative to the wide-angle end; and the interval between the fourth and fifth lens groups is increased at the telephoto end relative to the wide-angle end, and at the time of focusing a near object point from a remote object point, the second lens group is moved.

Abstract: In a zoom lens of a fixed total length, at the time of changing the magnification from the wide-angle end toward the telephoto end, the first lens group is anchored while the second lens group is moved, and the third and fourth lens groups are moved so as to be located at the object side of the telephoto end relative to the wide-angle end, such that: the interval between the second and third lens groups is decreased at the telephoto end relative to the wide-angle end; the interval between the third and fourth lens groups is increased at the telephoto end relative to the wide-angle end; and the interval between the fourth and fifth lens groups is increased at the telephoto end relative to the wide-angle end, and at the time of focusing a near object point from a remote object point, the second lens group is moved.

Abstract: A zoom lens comprises a first lens unit G1 having a positive refractive power, a second lens unit G2 having a negative refractive power, a third lens unit G3 having a positive refractive power, a fourth lens unit G4 having a negative refractive power, a fifth lens unit G5, and a sixth lens unit G6 having a positive refractive power. Zooming from a wide angle end to a telephoto end is carried out by changing a distance between the lens units, and a distance between the first lens unit G1 and the third lens unit G3 narrows at the telephoto end than at the wide angle end, and the first lens unit G1 is stationary at the time of zooming from the wide angle end to the telephoto end, and lens units from the second lens unit G2 to the fifth lens unit G5 move.

Abstract: In a zoom lens of a fixed total length, at the time of changing the magnification from the wide-angle end toward the telephoto end, the first lens group is anchored while the second lens group is moved, and the third and fourth lens groups are moved so as to be located at the object side of the telephoto end relative to the wide-angle end, such that: the interval between the second and third lens groups is decreased at the telephoto end relative to the wide-angle end; the interval between the third and fourth lens groups is increased at the telephoto end relative to the wide-angle end; and the interval between the fourth and fifth lens groups is increased at the telephoto end relative to the wide-angle end, and at the time of focusing a near object point from a remote object point, the second lens group is moved.

Abstract: A wide angle optical system including a first lens group of negative refractive power and a second lens group of positive refractive power arranged in the above-mentioned order from the object side. The second lens group includes a cemented doublet SU21; an aperture diaphragm; a lens SU22; and a biconvex lens L25 arranged in the above-mentioned order from the object side, and largest ones of air spaces on the axis being front and rear spaces of the aperture diaphragm except the back focal length. The wide angle optical system is divided into the first lens group and the second lens group at the second largest air space operating as a boundary.

Abstract: In a zoom lens of a fixed total length, at the time of changing the magnification from the wide-angle end toward the telephoto end, the first lens group is anchored while the second lens group is moved, and the third and fourth lens groups are moved so as to be located at the object side of the telephoto end relative to the wide-angle end, such that: the interval between the second and third lens groups is decreased at the telephoto end relative to the wide-angle end; the interval between the third and fourth lens groups is increased at the telephoto end relative to the wide-angle end; and the interval between the fourth and fifth lens groups is increased at the telephoto end relative to the wide-angle end, and at the time of focusing a near object point from a remote object point, the second lens group is moved.

Abstract: In a zoom lens of a fixed total length, at the time of changing the magnification from the wide-angle end toward the telephoto end, the first lens group is anchored while the second lens group is moved, and the third and fourth lens groups are moved so as to be located at the object side of the telephoto end relative to the wide-angle end, such that: the interval between the second and third lens groups is decreased at the telephoto end relative to the wide-angle end; the interval between the third and fourth lens groups is increased at the telephoto end relative to the wide-angle end; and the interval between the fourth and fifth lens groups is increased at the telephoto end relative to the wide-angle end, and at the time of focusing a near object point from a remote object point, the second lens group is moved.

Abstract: A wide angle optical system includes: a first lens group of negative refractive power; and a second lens group of positive refractive power; the first lens group and the second lens group being arranged in the above-mentioned order from the object side; the second lens group including: a cemented doublet SU21; an aperture diaphragm; a lens SU22; and a biconvex lens L25; the cemented doublet, the aperture diaphragm, the lens and the biconvex lens being arranged in the above-mentioned order from the object side; the largest ones of the air spaces on the axis being the front and rear spaces of the aperture diaphragm except the back focal length; the wide angle optical system being divided into the first lens group and the second lens group at the second largest air space operating as a boundary.

Abstract: The invention relates to an image pickup system comprising an electronic view finder suitable for achieving compactness and having a sufficient viewing angle of field and satisfactory optical performance. The image pickup system comprises an image pickup device, an image display device for displaying an image, a controller for converting image formation obtained from the image pickup device into a signal that enables the image information to be formed on the image display device, and a viewing optical system for guiding an image displayed on the display device to a viewer's eye. The viewing optical system comprises at least three lenses.

Abstract: The invention relates to an image pickup system comprising an electronic view finder suitable for achieving compactness and having a sufficient viewing angle of field and satisfactory optical performance. The image pickup system comprises an image pickup device, an image display device for displaying an image, a controller for converting image formation obtained from the image pickup device into a signal that enables the image information to be formed on the image display device, and a viewing optical system for guiding an image displayed on the display device to a viewer's eye. The viewing optical system comprises at least three lenses.

Abstract: The invention relates to an image pickup system comprising an electronic view finder suitable for achieving compactness and having a sufficient viewing angle of field and satisfactory optical performance. The image pickup system comprises an image pickup device, an image display device for displaying an image, a controller for converting image formation obtained from the image pickup device into a signal that enables the image information to be formed on the image display device, and a viewing optical system for guiding an image displayed on the display device to a viewers eye. The viewing optical system comprises at least three lenses.

Abstract: The invention relates to an image pickup system comprising an electronic view finder suitable for achieving compactness and having a sufficient viewing angle of field and satisfactory optical performance. The image pickup system comprises an image pickup device, an image display device for displaying an image, a controller for converting image formation obtained from the image pickup device into a signal that enables the image information to be formed on the image display device, and a viewing optical system for guiding an image displayed on the display device to a viewer's eye. The viewing optical system comprises at least three lenses.

Abstract: A zoom lens system comprises, in order from an object side, a positive first lens unit including a reflective optical element, a negative second lens unit, a positive third lens unit and a positive fourth lens unit, or a positive first lens unit, a negative second lens unit, a positive third lens unit, a negative fourth lens unit and a positive fifth lens unit. During zooming from a wide-angle end toward a telephoto end, the first lens unit is fixed, at least the second and third lens units move, and a space between the lens units changes. The second lens unit is positioned closer to an image-surface side in the telephoto end than in the wide-angle end, and the third lens unit is positioned closer to the object side in the telephoto end than in the wide-angle end. An image taking apparatus including the zoom lens system is also disclosed.

Abstract: The invention relates to a zoom lens in which tweaks to the mode of movement of lens groups and the first lens group contribute more to making sure the desired zoom ratio and optical performances and ensuring that the whole length of the zoom lens is kept short while carrying it around. The zoom lens comprises a positive first lens group G1, a negative second lens group G2 and a positive third lens group G3, and includes an aperture stop S located between the second G2 and the third lens group G3. Upon zooming from the wide-angle end to the telephoto end, the first lens group G1 moves in unison, and the second lens group G2 moves in unison. The first G1 and the second lens group G2 are positioned nearer to the object side at the telephoto end than at the wide-angle end, with an increasing spacing between the first G1 and the second lens group G2 and a decreasing spacing between the second G2 and the third lens group G3.

Abstract: A zoom lens system comprises, in order from an object side, a positive first lens unit including a reflective optical element, a negative second lens unit, a positive third lens unit and a positive fourth lens unit, or a positive first lens unit, a negative second lens unit, a positive third lens unit, a negative fourth lens unit and a positive fifth lens unit. During zooming from a wide-angle end toward a telephoto end, the first lens unit is fixed, at least the second and third lens units move, and a space between the lens units changes. The second lens unit is positioned closer to an image-surface side in the telephoto end than in the wide-angle end, and the third lens unit is positioned closer to the object side in the telephoto end than in the wide-angle end. An image taking apparatus including the zoom lens system is also disclosed.

Abstract: The invention relates to an image pickup system comprising an electronic view finder suitable for achieving compactness and having a sufficient viewing angle of field and satisfactory optical performance. The image pickup system comprises an image pickup device, an image display device for displaying an image, a controller for converting image formation obtained from the image pickup device into a signal that enables the image information to be formed on the image display device, and a viewing optical system for guiding an image displayed on the display device to a viewer's eye. The viewing optical system comprises at least three lenses.