摘要:
A camera system comprising a photographic lens having a plurality of lens units movable along a photographic optical axis when zooming, and a finder optic having a plurality of lens units movable along a finder optical axis when zooming, wherein the amounts of zooming movement of at least one of the lens units of the photographic lens and at least one of the lens units of the finder optic are the same.
摘要:
A varifocal lens is disclosed, comprising, from front to rear, a first lens unit of negative power, a second lens unit of positive power, and a third lens unit of negative power, all these lenses being moved along a common optical axis when the focal length of the entire lens system varies, wherein all the lens units each are constructed with either one lens, or two lenses, the total number of lenses being limited to 3 or 4, while still maintaining good optical performance.
摘要:
A zoom lens comprising, from front to rear, a first lens unit of negative power, a second lens unit of positive power and a third lens unit of negative power, the second and third lens units being moved to effect zooming, and the third lens unit having its focal length f.sub.3 laid in the following range:0.5 f.sub.W
摘要:
The disclosed zoom lens includes, from front to rear, a first lens unit of positive power, a second lens unit of negative power, a third lens unit of positive power, and a fourth lens unit. When zooming, the first and third lens units are axially moved independently of each other, the second lens unit remains stationary, and the fourth lens unit is axially moved but changes the direction of advance at an intermediate point in the zooming range.
摘要:
Disclosed is a two-component zoom objective having a first lens component of negative power and a second lens component of positive power with the variable air separation between the first and second components effecting zooming. The aforesaid first lens component is constructed with four lenses. The first lens counting from the front is given an aspheric surface, and the air lens defined by the second and third lenses counting from the front and the four lenses in the aforesaid first lens component are appropriately configured to increase the angular field up to an ultrawide angle, while still permitting good correction of aberrations.
摘要:
An anti-fog article is obtained by coating a substrate with an anti-fog coating material to form thereon an anti-fog coating film that is hydrophillic, moisture-absorptive, insoluble and excellent in surface hardness. The anti-fog coating material contains a polyacrylic acid compound, polyvinyl alcohol and acetylacetone, and optionally sodium silicate.
摘要:
Disclosed herein is an anti-fogging coating material comprising at least one selected from the group consisting of an inorganic alkoxide, a hydrolysate of the inorganic alkoxide and a polycondensate of the hydrolysate of the inorganic alkoxide, a polyacrylic, and polyvinyl alcohol.
摘要:
In the disclosed optical system of variable magnification power, at least one component A of two components A and B has its refractive power varied so that the focal length of the entire system can be continuously varied throughout a range while maintaining the position of the image plane constant throughout the range.
摘要:
A zoom lens whose first lens group, counting from front, has a negative refractive power and moves axially in differential relation to a following lens group to effect zooming, wherein the first lens group is constructed with a lens unit of negative power followed by another lens unit of positive power, whereby for focusing purposes, the negative lens unit is axially moved, while the positive lens unit is held stationary, to improve the stabilization of aberration correction throughout the entire focusing range.
摘要:
A zoom lens including, from front to rear, a first lens unit of negative power and a second lens unit of positive power with the separation therebetween being varied to effect zooming. The first lens unit is moved to effect focusing, wherein with the first lens unit focusing a finite object distance on the wide angle side, the second lens unit moves rearward to obtain focal lengths beyond the zooming range.