Abstract: In a zoom lens system for use with a compact camera having a wide coverage of angles that comprises, in order from the object side, a first lens group having a positive focal length and which performs zooming by changing the distance beween the first and second lens groups, the said first lens group comprises, in order from the object side, a front subgroup 1F having a positive focal length, a diaphragm stop and a positive rear subgroup 1R with a small power, and the first lens in the front subgroup 1F is a negative lens, with the specific conditions.

Abstract: A zoom lens system for use with a compact camera is disclosed which has a wide coverage of angles and which comprises, in order from the object side, a first lens group having a positive focal length and a second lens group having a negative focal length and which performs zooming by changing the distance between the first and second lens group. The first lens group comprises, in order form the object side, a subgroup 1a having a negative focal length and a subgroup 1b having a positive focal length. The subgroup 1a is composed of at least two lens elements including a negative first lens element on the object side and a meniscus lens element on the image side which has a concave surface directed toward the object with a large curvature and a convex surface directed toward the image with a large curvature. The subgroup 1a further satisfies the following condition:-0.5<f.sub.1G /f.sub.1 .ltoreq.0 (1)wheref.sub.1G : the focal length of the first lens group; andf.sub.

Abstract: A cemented lens consists of a lens that is tinted and/or contains a UV absorber, and a second lens that is neither tinted nor contains any UV absorber. The cemented lens is formed by placing the two lens elements together with a UV-curable adhesive between them, and then directing UV radiation through the first lens to cure the adhesive.

Abstract: An ocular system is disclosed which is composed of at least three lens elements for constituting, in order from the eye side, at least first and second lens units. At least one of the lens elements is made of resin. Two of the lens elements are substantially cemented together. In addition, an aspherical plastic lens is effectively used in the system.

Abstract: A device for admitting light into a photodetecting apparatus such as an automatic white balance sensor includes a light-diffusing plate having a light admitting face for receiving light and a light issuing face from which diffuse light emerges. A reflecting layer is formed on at least a surface of the light-diffusing plate which is opposite the light admitting face.

Abstract: A copying lens system of a three-unit/three-element composition that can be made from relatively inexpensive optical materials and which exhibits satisfactory performance at copying ratios ranging from about 0.5 to 2.0. The lens system includes, in order from the object side, a first lens of positive meniscus having a convex surface directed to the object, a negative second lens having a concave surface on both sides, and a positive third lens having a convex surface on both sides. The lens system satisfies the following conditions:(1) 1.70<n.sub.1 +.nu..sub.1 /200.ltoreq.1.93(2) 0.10<n.sub.3 -n.sub.1(3) 0.06<d.sub.t /f.sub.t 0.11(4) 0.60<-r.sub.3 /r.sub.4 <1.05(5) 1.40<-r.sub.5 /r.sub.6 <2.70wheref.sub.t : the focal length of the overall system;n.sub.i : the refractive index of the ith lens at the d-line;.nu..sub.i : the Abbe number of the i.sup.th lens;r.sub.j : the radio of the curvature of the j.sup.th lens; andd.sub.t : the overall length of the system.

Abstract: A zoom lens system comprising, in order from the object side, a first lens group that includes at least three lens elements and that has a negative overall power and a second lens group that includes at least four lens elements, with the negative lens element of the greatest powre being cemented to the adjacent positive lens element, and that has a positive overall power. The zoom lens system is capable of changing its focal length by adjusting the distance between the first and second lens groups. The zoom lens system satisfies the specific conditions.

Abstract: A device for use in an apparatus for demodulating the signal reproduced from a recording medium in a still video camera or the like in which the phase of the demodulated signal is always accurately detected. Horizontal periods in which the respective line-sequential color difference signals B-Y and R-Y are present are discriminated, and a timer is operated during periods when the B-Y signal is present. Data is read from the reproduced modulated signal at predetermined points within a half cycle of the waveform of the signal as designated by outputs of the timer.

Abstract: A method of measuring a refractive index distribution of a lens is disclosed which comprises, immersing a glass sample and a lens under test within a matching fluid whose refractive index differs slightly from that of the glass to be tested, the glass sample having a refractive index and a shape which are both known and the lens to be tested having an unknown refractive index but a known shape, allowing coherent light to pass through the glass sample and the lens under test; superposing the transmitted light wave on a reference light wave to generate interference fringes, outputting the intensity distribution of interference fringes that are generated by the light wave that has passed through the glass sample, determining the refractive index of the matching fluid on the basis of the resulting output, outputting the intensity distribution of interference fringes that are generated by the light wave that has passed through the lens under test; separating from the resulting output the defocus term and aberratio

Abstract: A surface treating composition for a reflection preventing film comprising at least one surface treating agent selected from the group consisting of a reactive organic polysiloxane compound containing an amino group and a reactive organic polysiloxane compound containing an epoxy group, and a method for treating a reflection preventing film using such a surface treating composition.

Abstract: A method for producing a dental and medical bone prosthesis comprising the step of: adding an aqueous acidic solution of an organic or inorganic acid, such as phosphoric acid, citric acid, or acetic acid, to a fixable granulated bone prosthesis comprising at least one of .alpha.-tricalcium phosphate and tetracalcium phosphate; and a dental and medical bone prosthesis produced thereby.

Abstract: An electronic flash control device makes sure that the emission of light of an electronic flash is not impaired by a noise component signal prior to generation of a suitable quantity of light by the flash. A trigger signal is applied by the control device to allow the flash to emit light. An enable signal is supplied to a quenching circuit a predetermined time after the noise of the trigger signal has been produced. When the quantity of light from an object to be photographed by the camera reaches a certain value and the enable signal occurs, the quench circuit suppresses the emission of light by the electronic flash.

Abstract: An oriented shaped article of a calcium phosphate type compound is disclosed, in which at least two crystallographic axes of the primary particles of which the shaped article is composed each is oriented in one direction, respectively, in at least the surface of said article. A sinter of the oriented shaped article and a processes for producing the article and the sinter are also disclosed.

Abstract: An apatite coated article comprising a substrate having thereon an apatite layer which is formed by flame spraying apatite powder at from about 2,000.degree. to 4,000.degree. C., and a process for producing such an apatite coated article.

Abstract: In an auto-focus camera, the focus position of the lens is locked to permit the user to let go of the shutter button, with subsequent depression of the shutter button resulting in photography at the retained focus position of the lens without further lens driving.

Abstract: A support for a biomedical implant device in which the support has a surface layer composed of a biocompatible calcium phosphate material such as sintered hydroxyapatite with a porosity of 50-60% and pore size of 0.5-500 micrometers. Preferably, the surface layer is formed with projections or recesses of a few hundred micrometers size.