Abstract: A zoom lens which has a high variable magnification ratio and high optical performance and an optical apparatus having the zoom lens are provided. A zoom lens according to an embodiment of the present invention comprises, in order from an object side, a first, second, third, and a fourth lens unit respectively having positive, negative, positive and positive optical powers. For zooming from the wide angle end to the telephoto end, the first lens unit is moved to an object side, the second lens unit is moved to an image plane side, the third lens unit is moved to the object side, and the fourth lens unit is moved to the object side. The third lens unit is movable in a direction perpendicular to the optical axis to correct an image blur.

Abstract: This specification discloses a zoom lens system provided, in succession from the front to the rear, with a first lens unit of negative optical power, a second lens unit of positive optical power and, a third lens unit of positive optical power.

Abstract: A reflecting type of zoom optical system comprises a plurality of optical elements each of which includes a transparent body and two refracting surfaces and a plurality of reflecting surfaces formed on the transparent body and is arranged so that a light beam enters the transparent body from one of the two refracting surfaces, repeatedly undergoes reflection by the plurality of reflecting surfaces, and exits from the other of the two refracting surfaces, and/or a plurality of optical elements on each of which a plurality of reflecting surfaces made from surface reflecting mirrors are integrally formed, and each of which is arranged so that an entering light beam repeatedly undergoes reflection by the plurality of reflecting surfaces and exits from the optical element.

Abstract: A zoom lens is constructed with, in order from an object side to an image side, a first lens unit of negative optical power, the first lens unit including a negative meniscus lens having a concave surface facing the image side and a positive meniscus lens having a convex surface facing the object side, a second lens unit of positive optical power, the second lens unit including a cemented lens of positive optical power as a whole disposed on the most image side of the second lens unit, and a lens having a concave surface facing the image side and adjoining a surface on the object side of the cemented lens, and a third lens unit of positive optical power, wherein a separation between the first lens unit and the second lens unit and a separation between the second lens unit and the third lens unit are varied to effect variation of magnification.

Abstract: A reflecting type of zoom optical system comprises a plurality of optical elements each of which includes a transparent body and two refracting surfaces and a plurality of reflecting surfaces formed on the transparent body and is arranged so that a light beam enters the transparent body from one of the two refracting surfaces, repeatedly undergoes reflection by the plurality of reflecting surfaces, and exits from the other of the two refracting surfaces, and/or a plurality of optical elements on each of which a plurality of reflecting surfaces made from surface reflecting mirrors are integrally formed, and each of which is arranged so that an entering light beam repeatedly undergoes reflection by the plurality of reflecting surfaces and exits from the optical element.

Abstract: A zoom optical system comprises a plurality of optical elements. The plurality of optical elements include a first optical element having two refracting surfaces and a plurality of reflecting surfaces formed in a transparent body, being arranged such that a light beam enters an inside of the transparent body from one of the two refracting surfaces and, after being successively reflected from the plurality of reflecting surfaces, exits from the other of the two refracting surfaces, and/or a second optical element having a plurality of surface mirrors integrally formed and decentered relative to one another, being arranged such that an incident light beam exits therefrom after being successively reflected from reflecting surfaces of the plurality of surface mirrors, and a third optical element composed of a plurality of coaxial refracting surfaces.

Abstract: A zoom lens is constructed with, in order from an object side to an image side, a first lens unit of negative optical power, the first lens unit including a negative meniscus lens having a concave surface facing the image side and a positive meniscus lens having a convex surface facing the object side, a second lens unit of positive optical power, the second lens unit including a cemented lens of positive optical power as a whole disposed on the most image side of the second lens unit, and a lens having a concave surface facing the image side and adjoining a surface on the object side of the cemented lens, and a third lens unit of positive optical power, wherein a separation between the first lens unit and the second lens unit and a separation between the second lens unit and the third lens unit are varied to effect variation of magnification.

Abstract: A zoom lens which suppresses variations of an exit pupil and is telecentric on the image side in the whole range of zooming is to be disclosed.

Abstract: The disclosed zoom lens includes a first lens unit having a negative optical power, a second lens unit having a positive optical power, and a third lens unit having a positive optical power in order from an object side to an image side. The zoom lens has a shorter interval between the first lens unit and the second lens unit and a longer interval between the second lens unit and the third lens unit on a telephoto end than an interval between the first lens unit and the second lens unit and an interval between the second lens unit and the third lens unit on a wide angle end, respectively.

Abstract: A zoom lens is constructed with, in order from an object side to an image side, a first lens unit of negative optical power, the first lens unit including a negative meniscus lens having a concave surface facing the image side and a positive meniscus lens having a convex surface facing the object side, a second lens unit of positive optical power, the second lens unit including a cemented lens of positive optical power as a whole disposed on the most image side of the second lens unit, and a lens having a concave surface facing the image side and adjoining a surface on the object side of the cemented lens, and a third lens unit of positive optical power, wherein a separation between the first lens unit and the second lens unit and a separation between the second lens unit and the third lens unit are varied to effect variation of magnification.

Abstract: A zoom optical system comprises a plurality of optical elements. The plurality of optical elements include a first optical element having two refracting surfaces and a plurality of reflecting surfaces formed in a transparent body, being arranged such that a light beam enters an inside of the transparent body from one of the two refracting surfaces and, after being successively reflected from the plurality of reflecting surfaces, exits from the other of the two refracting surfaces, and/or a second optical element having a plurality of surface mirrors integrally formed and decentered relative to one another, being arranged such that an incident light beam exits therefrom after being successively reflected from reflecting surfaces of the plurality of surface mirrors, and a third optical element composed of a plurality of coaxial refracting surfaces.

Abstract: A zoom optical system comprises a plurality of optical elements. The plurality of optical elements include a first optical element having two refracting surfaces and a plurality of reflecting surfaces formed in a transparent body, being arranged such that a light beam enters an inside of the transparent body from one of the two refracting surfaces and, after being successively reflected from the plurality of reflecting surfaces, exits from the other of the two refracting surfaces, and/or a second optical element having a plurality of surface mirrors integrally formed and decentered relative to one another, being arranged such that an incident light beam exits therefrom after being successively reflected from reflecting surfaces of the plurality of surface mirrors, and a third optical element composed of a plurality of coaxial refracting surfaces.

Abstract: A reflecting type of zoom optical system comprises a plurality of optical elements each of which includes a transparent body and two refracting surfaces and a plurality of reflecting surfaces formed on the transparent body and is arranged so that a light beam enters the transparent body from one of the two refracting surfaces, repeatedly undergoes reflection by the plurality of reflecting surfaces, and exits from the other of the two refracting surfaces, and/or a plurality of optical elements on each of which a plurality of reflecting surfaces made from surface reflecting mirrors are integrally formed, and each of which is arranged so that an entering light beam repeatedly undergoes reflection by the plurality of reflecting surfaces and exits from the optical element.

Abstract: A variable magnification optical system includes at least three optical units which are a first moving optical unit, a fixed optical unit and a second moving optical unit. The three optical units are arranged in that order in a propagation direction of light, and a variation of magnification is effected by a relative movement between the first moving optical unit and the second moving optical unit.

Abstract: In order to provide a zoom lens which has excellent optical performance with a compact configuration using a small number of constituent lenses, a zoom lens according to the present invention comprises a first lens unit having a negative optical power, a second lens unit having a positive optical power, and a third lens unit having a positive optical power, which are sequentially arranged from the object side, wherein the gap between the first and second lens units is decreased, the space between the second and third lens units is increased in zooming from the side angle end to the telephoto end, the third lens unit has a cemented lens formed by cementing a positive lens element to a negative lens element, and is moved along the optical axis for zooming, and letting NLi be the number of lensess constituting the ith lens unit, a condition,

Abstract: An optical system of reflecting type according to the invention comprises an optical element composed of a transparent body having an entrance surface, an exit surface and at least three curved reflecting surfaces of internal reflection, wherein a light beam coming from an object and entering at the entrance surface is reflected from at least one of the reflecting surfaces to form a primary image within the optical element and is, then, made to exit from the exit surface through the remaining reflecting surfaces to form an object image on a predetermined plane, and wherein 70% or more of the length of a reference axis in the optical element lies in one plane.

Abstract: A disclosed optical apparatus comprises an optical unit including a light entrance surface, light reflecting surfaces and a light exit surface all of which are integrally formed of transparent material, and the optical unit has in its interior an internal refracting surface for refracting light. Since a light beam passes through the optical unit from the light entrance surface to the light exit surface via the internal refracting surface and the light reflecting surfaces along a bent optical path, the optical apparatus is reduced in size and improved in optical performance, particularly, well corrected in chromatic aberration. Another disclosed optical apparatus is arranged to achieve zooming by using a plurality of optical units each of which is similar to the aforesaid optical unit.

Abstract: A reflecting-type optical system according to the invention includes an optical element composed of a transparent body having an entrance surface, an exit surface and at least three curved reflecting surfaces of internal reflection. A light beam coming from an object and entering at the entrance surface is reflected from at least one of the reflecting surfaces to form a primary image within the optical element and is, then, made to exit from the exit surface through the remaining reflecting surfaces to form an object image on a predetermined plane. In the optical system, 70% or more of the length of a reference axis in the optical element lies in one plane.

Abstract: An optical element includes an incidence surface, one or more reflecting surfaces reflecting light from the incident surface, an emergence surface, and off-axial curved surfaces causing the light to emerge from the emergence surface. At least one of the incidence surface, the emergence surface and the one or more reflecting surfaces is a surface having diffracting action. The surface having the diffracting action is a curved surface.

Abstract: An image pickup optical system includes an optical unit having a light incidence surface on which a light is incident, a light reflecting surface reflecting the light incident from the light incidence surface and having a curvature, and a light emergence surface from which the light reflected by the light reflecting surface emerges, and a transparent optical member disposed near the surface position of at least one of the light incidence surface and the light emergence surface. The optical member is adhesively fixed to the optical unit to thereby make any special holding member for the optical member relative to the optical unit unnecessary.