Abstract: A zoom lens system includes, in order from an object side, a first lens unit having a negative refractive power, a second lens unit having a positive refractive power, and a third lens unit having a positive refractive power. During zooming from a wide-angle end to a telephoto end, a space between the first lens unit and the second lens unit narrows, at least the second lens unit moves only toward the object side, and the third lens unit is constituted of one positive lens.

Abstract: The invention relates to a zoom lens and an imaging apparatus, and more particularly to a slimmed-down zoom lens well fit for imaging apparatus inclusive of video cameras and digital cameras. The zoom lens comprises, in order from its object side, a first lens group having negative refracting power, a second lens group having positive refracting power, a third lens group having negative refracting power and a fourth lens group having positive refracting power. The first lens group consists of one negative component wherein one negative lens and one positive lens are cemented together. Upon zooming from the wide-angle end to the telephoto end and the second lens group moves toward the object side with a decreasing spacing between the first lens group and the second lens group, a changing spacing between the second lens group and the third lens group and a changing spacing between the third lens group and the fourth lens group.

Abstract: An optical system is presented that enables images of a wide range of natural subjects to be well reproduced with their colors, and provides an image pickup system including, at least, an image pickup optical system, an electronic image pickup device having three or more different spectral characteristics to obtain a color image, and a controller for implementing signal processing or image processing on the basis of an output from the electronic image pickup device. The optical element that takes part in determining the focal length in the image pickup system includes an optical element making use of a refraction phenomenon alone.

Abstract: An optical system is presented that enables images of a wide range of natural subjects to be well reproduced with their colors, and provides an image pickup system including, at least, an image pickup optical system, an electronic image pickup device having three or more different spectral characteristics to obtain a color image, and a controller for implementing signal processing or image processing on the basis of an output from the electronic image pickup device. The optical element that takes part in determining the focal length in the image pickup system includes an optical element making use of a refraction phenomenon alone.

Abstract: An optical system enables images to be well reproduced with their colors, and provides an image pickup system including an image pickup optical system, an electronic image pickup device to obtain a color image and a controller for implementing signal processing or image processing on the basis of an output from the electronic image pickup device. The optical element that takes part in the determination of a focal length includes an optical element making use of a refraction phenomenon alone. The 400-nm wavelength input/output ratio is 10% or less with respect to an input-output ratio for a 400-nm to 800-nm wavelength at which an output signal strength ratio with respect to an input quantity of light is highest when the input quantity of light is defined by the quantity of a light beam emanating from the same object point and entering the image pickup optical system and the output signal strength is defined by the strength of a signal produced from the controller in response to the light beam.

Abstract: The invention relates to a zoom lens and an imaging apparatus, and more particularly to a slimmed-down zoom lens well fit for imaging apparatus inclusive of video cameras and digital cameras. The zoom lens comprises, in order from its object side, a first lens group having negative refracting power, a second lens group having positive refracting power, a third lens group having negative refracting power and a fourth lens group having positive refracting power. The first lens group consists of one negative component wherein one negative lens and one positive lens are cemented together. Upon zooming from the wide-angle end to the telephoto end and the second lens group moves toward the object side with a decreasing spacing between the first lens group and the second lens group, a changing spacing between the second lens group and the third lens group and a changing spacing between the third lens group and the fourth lens group.

Abstract: An electronic imaging apparatus includes a zoom optical system having, in order from the object side, a first lens unit with positive power, a second lens unit with negative power, and an aperture stop, in which the first lens unit is composed of a single positive power unit and the second lens unit has a single negative lens element located at the most object-side position, both surfaces of which are concave, and a positive lens component located at the most image-side position; an electronic image sensor located on the image side of the zoom optical system; and an image processing section electrically processing image data obtained by the electronic image sensor to change the form thereof.

Abstract: The invention relates to a zoom lens favorable for offering a tradeoff between slimming down a lens system upon received in an associated lens mount and making sure a small F-number. There is a zoom lens provided, which comprises, in order from its object side, a first lens group G1 having negative refracting power, a second lens group G2 having positive refracting power, and a third lens group G3 having positive refracting power. Upon zooming from a wide-angle end to a telephoto end, the first second and third lens groups G1, G2 and G3 each move along an optical axis while a spacing between the first lens group and the second lens group becomes narrow and a spacing between the second lens group and the third lens group becomes wide. The first lens group G1 comprises one single lens that is a double-concave negative lens or two lenses: a double-concave negative lens and a positive lens. The second lens group G2 comprises two positive lenses and one negative lens.

Abstract: A three-unit zoom lens system comprising, in order from an object side, a first lens unit having a negative refractive power; a second lens unit having a positive refractive power; and a third lens unit having a positive or negative refractive power, wherein during magnification change from a wide-angle end to a telephoto end, a space between the first lens unit and the second lens unit narrows, the second lens unit and the third lens unit move toward the only object side, and a space between the second lens unit and the third lens unit changes during a focusing operation.

Abstract: An electronic imaging apparatus includes a zoom optical system having, in order from the object side, a first lens unit with positive power, a second lens unit with negative power, and an aperture stop, in which the first lens unit is composed of a single positive power unit and the second lens unit has a single negative lens element located at the most object-side position, both surfaces of which are concave, and a positive lens component located at the most image-side position; an electronic image sensor located on the image side of the zoom optical system; and an image processing section electrically processing image data obtained by the electronic image sensor to change the form thereof.

Abstract: An electronic imaging apparatus includes a zoom optical system having, in order from the object side, a first lens unit with positive power, a second lens unit with negative power, and an aperture stop, in which the first lens unit is composed of a single positive power unit and the second lens unit has a single negative lens element located at the most object-side position, both surfaces of which are concave, and a positive lens component located at the most image-side position; an electronic image sensor located on the image side of the zoom optical system; and an image processing section electrically processing image data obtained by the electronic image sensor to change the form thereof.

Abstract: A zoom lens system comprising, a first negative lens unit; a second positive lens unit; and a third negative lens unit, wherein a space between the second and third lens units changes during magnification change or focusing operation; the second lens unit and the third lens unit move only to the object side during the magnification change from a wide-angle end to a telephoto end so that a space between the first and second lens units is narrower in the telephoto end than in the wide-angle end; the first lens unit comprises a negative lens and a positive lens; the second lens unit comprises at most three lenses; the third lens unit comprises a negative lens; and the following condition (1) is satisfied: 0.7<Cj(t)/Cj(w)<1.2.

Abstract: An image taking apparatus is equipped with a zoom lens system which comprises: a first lens unit having a positive refractive power; a second lens unit having a negative refractive power; a third lens unit having a positive refractive power; and a fourth lens unit having a positive refractive power, at least the first lens unit, the second lens unit, and the third lens unit move during zooming from a wide-angle end to a telephoto end so that a space between the first lens unit and the second lens unit increases, a space between the second lens unit and the third lens unit decreases, and a space between the third lens unit and the fourth lens unit increases, and the first lens unit is arranged closer to an image side in the wide-angle end than that in the telephoto end.

Abstract: The invention relates to a zoom lens favorable for offering a tradeoff between slimming down a lens system upon received in an associated lens mount and making sure a small F-number. There is a zoom lens provided, which comprises, in order from its object side, a first lens group G1 having negative refracting power, a second lens group G2 having positive refracting power, and a third lens group G3 having positive refracting power. Upon zooming from a wide-angle end to a telephoto end, the first second and third lens groups G1, G2 and G3 each move along an optical axis while a spacing between the first lens group and the second lens group becomes narrow and a spacing between the second lens group and the third lens group becomes wide. The first lens group G1 comprises one single lens that is a double-concave negative lens or two lenses: a double-concave negative lens and a positive lens. The second lens group G2 comprises two positive lenses and one negative lens.

Abstract: A zoom lens system includes a first group G1 of positive power, a second group G2 of negative power, a third group G3 of positive power and a fourth group G4 of positive power. Upon zooming, at least the first group G1, the second group G2 and the third group G3 move on an optical axis in such a way that, at a telephoto end with respect to a wide-angle end, the space between the first group G1 and the second group G2 and the third group G3 becomes narrow and the space between the third group G3 and the fourth group G4 becomes wide. The zoom lens system satisfies a condition that defines the ratio of the total length (length from the first surface of the lens system to an image plane) to the focal length of the zoom lens system at the wide-angle end.

Abstract: A zoom lens system comprising, a first negative lens unit; a second positive lens unit; and a third negative lens unit, wherein a space between the second and third lens units changes during magnification change or focusing operation; the second lens unit and the third lens unit move only to the object side during the magnification change from a wide-angle end to a telephoto end so that a space between the first and second lens units is narrower in the telephoto end than in the wide-angle end; the first lens unit comprises a negative lens and a positive lens; the second lens unit comprises at most three lenses; the third lens unit comprises a negative lens; and the following condition (1) is satisfied: 0.7<Cj(t)/Cj(w)<1.2 .

Abstract: A zoom lens system comprising, in order from an object side, a first lens unit having a negative refractive power, a second lens unit having a positive refractive power and a third lens unit having a positive refractive power, wherein during zooming from a wide-angle end to a telephoto end, a space between the first lens unit and the second lens unit narrows, at least the second unit move only toward the object side, and the third lens unit G3 is constituted of one positive lens.

Abstract: A three-unit zoom lens system comprising, in order from an object side, a first lens unit having a negative refractive power; a second lens unit having a positive refractive power; and a third lens unit having a positive or negative refractive power, wherein during magnification change from a wide-angle end to a telephoto end, a space between the first lens unit and the second lens unit narrows, the second lens unit and the third lens unit move toward the only object side, and a space between the second lens unit and the third lens unit changes during a focusing operation.

Abstract: An optical system is presented that enables images of a wide range of natural subjects to be well reproduced with their colors, and provides an image pickup system including, at least, an image pickup optical system, an electronic image pickup device having three or more different spectral characteristics to obtain a color image, and a controller for implementing signal processing or image processing on the basis of an output from the electronic image pickup device. The optical element that takes part in determining the focal length in the image pickup system includes an optical element making use of a refraction phenomenon alone.

Abstract: An optical system is presented that enables images of a wide range of natural subjects to be well reproduced with their colors, and provides an image pickup system including, at least, an image pickup optical system, an electronic image pickup device having three or more different spectral characteristics to obtain a color image, and a controller for implementing signal processing or image processing on the basis of an output from the electronic image pickup device. The optical element that takes part in determining the focal length in the image pickup system includes an optical element making use of a refraction phenomenon alone.