Abstract: An optical element having a plastic substrate and an antireflection film of a &lgr;/4-&lgr;/2-&lgr;/4 or &lgr;/4-&lgr;/4-&lgr;/2-&lgr;/4 type (&lgr;=500 nm) provided in that order on the plastic substrate, wherein the layer of &lgr;/2 is a high-refraction equivalent film containing at least three layers and having a refractive index of from 1.80 to 2.40, and the even-numbered layer(s) of the equivalent film is an SiO2 layer or a layer in which SiO2 is a main component.

Abstract: A method for producing a composition for vapor deposition comprising sintering a vapor source mixture prepared by mixing vapor sources that contain titanium dioxide and niobium pentoxide. The method is capable of forming a high-refraction layer even in low-temperature vapor deposition on a substrate. An antireflection film is formed having good scratch resistance, good chemical resistance and good heat resistance, of which the heat resistance decreases little with time, that is useful in a variety of optical elements.

Abstract: A method for producing an optical element having a multi-layered antireflection film formed on a synthetic resin substrate, in which the antireflection film formed has good heat resistance, and its heat resistance lowers little with time. At least one high-refraction layer of the multi-layered anti-reflection film contains niobium oxide, zirconium oxide, yttrium oxide, and optionally aluminum oxide. High-refraction layers can be formed within a shorter period of time while not detracting from the good physical properties intrinsic to the layers.

Abstract: An optical element having a plastic substrate and an antireflection film of a &lgr;/4-&lgr;/2-&lgr;/4 or &lgr;/4-&lgr;/4-&lgr;/2-&lgr;/4 type (&lgr;=500 nm) provided in that order on the plastic substrate, wherein the layer of &lgr;/2 is a high-refraction equivalent film containing at least three layers and having a refractive index of from 1.80 to 2.40, and the even-numbered layer(s) of the equivalent film is an SiO2 layer or a layer in which SiO2 is a main component.

Abstract: A substrate holder (22) on which a plurality of optical lens base materials (24) are arranged is installed to be rotatable in a vacuum atmosphere and a vacuum processing chamber (16) for forming water repellent films on the surfaces of the optical lens base materials, and further a both sides simultaneous water repellency processing mechanism is installed in this vacuum processing chamber. In regard to the substrate holder (22), an upper side water repellency processing unit (30) and a lower side water repellency processing unit (40) are provided, and the upper side water repellency processing unit forms the water repellent film on the upper side of the optical lens base material, while the lower side water repellency processing unit forms the water repellent film on the lower side of the optical lens base material. This configuration forms the water repellent films simultaneously onto the both sides of the optical lens base material.

Abstract: Plastic optical devices in which an antireflection film (13) is coated on the surface of a plastic base material (10). The antireflection film (13) is a multi-layered film which is formed by depositing a first layer (131) on the side of the plastic base material substantially by a high-refractive material and the next layer (132) by a low-refractive material, and by alternately laminating those high-refractive materials and low-refractive materials. The surface of the optical lens base material (10) has curvature and a plurality of the optical lens base materials (10) are disposed horizontally at the positions of concentric circles in a circular plate holder (26) which is placed horizontally and is rotatable. A sputtering film deposition system comprises targets (31) facing to the surfaces of the optical lens base materials (10).

Abstract: Antireflection films are coated on the both sides of an optical lens by sputtering in a sputtering system. In a vacuum processing chamber (22) for performing the sputtering, a plurality of optical lens base materials are placed transversely on a substrate holder (26). The holder (26) is set rotatably in a vacuum atmosphere. The optical lens base materials are embedded to holes (26a) formed in the holder (26), facing their concave surface up, by using ring-shaped holding tools (52, 152). The height of the ring-shaped holding tool (52) is larger than the height of the edge of the optical lens base material (11) within the limits of 2 mm when the thickness of the lens edge of the optical lens base material is large. Part of the ring-shaped holding tool (152) which is put together with the upper surface of the optical lens base material (111) is tapered when the thickness of the lens edge of the optical lens base material is small.

Abstract: In an in-cylinder injection internal combustion engine which is placed in a selected one of a compression stroke injection mode in which fuel injection is conducted during a compression stroke, and a suction stroke injection mode in which fuel injection is conducted during a suction stroke, depending upon operating conditions of the engine, a fuel control device cut a fuel to be supplied to a combustion chamber of the engine when a certain fuel cut condition set depending upon the operating conditions of the engine is established, and resumes fuel injection in a compression stroke injection mode when a predetermined fuel cut return condition is established. In this fuel control device, when the fully closed state of a throttle valve is detected by an idle switch, or the engine speed is reduced by a large degree, the fuel injection is resumed in an intake stroke injection mode upon return from the fuel cut, so as to prevent undershoot of the engine speed.

Abstract: A fuel control device for cylinder injection type internal combustion engines which is capable of cutting off fuel supplying to a combustion chamber depending upon an operating state of the engine and suitable for use in cylinder injection type engines, in which a compression stroke mode can be selected for the purpose of enabling shifting to fuel cutoff and shifting to fuel injection from cutoff without incurring shock of switching in the engine.

Abstract: In order to securely prevent knocks from occurring upon starting and the like, while enhancing the compression ratio in a spark ignition type in-cylinder injection internal combustion engine which includes a fuel injection valve for directly injecting fuel into a combustion chamber, fuel is injected during a compression stroke in a specific operation region under an intermediate to high load to perform stratified combustion. Further provided is a control unit for driving and controlling the fuel injection valve such that, in the stratified combustion, prior to the fuel injection during the compression stroke, fuel is injected from the fuel injection valve during an intake stroke by such an amount that fuel fails to self-ignite.

Abstract: In an in-cylinder injection internal combustion engine which is placed in a selected one of a compression stroke injection mode in which fuel injection is conducted during a compression stroke, and a suction stroke injection mode in which fuel injection is conducted during a suction stroke, depending upon operating conditions of the engine, a fuel control device cut a fuel to be supplied to a combustion chamber of the engine when a certain fuel cut condition set depending upon the operating conditions of the engine is established, and resumes fuel injection in a compression stroke injection mode when a predetermined fuel cut return condition is established. In this fuel control device, when the fully closed state of a throttle valve is detected by an idle switch, or the engine speed is reduced by a large degree, the fuel injection is resumed in an intake stroke injection mode upon return from the fuel cut, so as to prevent undershoot of the engine speed.

Abstract: A control apparatus for a cylinder fuel injection internal combustion engine in which a compression stroke injection mode for carrying out fuel injection mainly in a compression stroke and a suction stroke injection mode for carrying out fuel injection mainly in a suction stroke can be selected in accordance with the operational condition of the engine. The apparatus aiming at enabling a suitable suction correcting amount to be set for each operational mode of the engine and the improvement of drivability thereby being improved.

Abstract: A control apparatus for an in-cylinder injection spark-ignition internal combustion engine, which includes a fuel injection valve for injecting a fuel directly into a combustion chamber and a spark plug for subjecting the fuel to spark ignition in the combustion chamber, and operates in an intake-stroke injection mode where the fuel is injected mainly in an intake stroke or a compression-stroke injection mode where the fuel is injected mainly in a compression stroke, comprises load correlation value calculation means for calculating a load correlation value of the internal combustion engine, ignition timing setting means for setting a reference ignition timing for the spark plug in accordance with the fuel injection mode and the load correlation value, and correction means for correcting the reference ignition timing in accordance with the operating state, the control apparatus further comprising correction limiting means for limiting the correction when the fuel injection mode is the compression-stroke injec

Abstract: When the rotation speed of an in-cylinder injection engine 1 reduces to a rotation speed for increasing the amount of air which has been set on a higher rotation speed side than a fuel supply-return rotation speed, the amount of air is increased. Thereafter, when the rotation speed of the in-cylinder injection engine 1 reduces to the fuel supply-return rotation speed, the supply of fuel is resumed in the fuel cut mode to securely prevent the rotation speed from lowering and to reduce a torque down during resumption of fuel-supply and deteriorated fuel consumption.

Abstract: A control apparatus for a cylinder-injection spark-ignition internal combustion engine, having a fuel injection valve for directly injecting fuel to a combustion chamber and controlling the fuel injection valve on the basis of either an intake stroke injection mode for effecting fuel injection mainly in the intake stroke and a compression stroke injection mode for effecting fuel injection mainly in the compression stroke. A fuel injection quantity correction device corrects at least the fuel injection quantity supplied to the combustion chamber and an intake air quantity correction device corrects the intake air quantity supplied to the combustion chamber so that the preset target idle speed is reached when an idle operation state is detected.

Abstract: An ignition timing control system is provided for an in-cylinder injection internal combustion engine to reduce a torque shock upon switching a fuel injection mode between a compression-stroke injection mode, in which an injection of fuel is performed primarily in a compression stroke, and an intake-stroke injection mode, in which an injection of fuel is performed primarily in an intake stroke, in accordance with an operation state of said internal combustion engine. The ignition timing control system is provided with an injection timing correction unit for correcting ignition timing of a spark plug, which is arranged in a combustion chamber, upon switching said fuel injection mode.

Abstract: In a combustion control device for an internal combustion engine provided with a plurality of fuel injection modes having different target air-fuel ratios, threshold values for detecting deterioration of combustion in the internal combustion engine are determined separately for each fuel injection mode depending on features of variation of combustion in the internal combustion engine in each fuel injection mode. Quantity of variation of combustion in the internal combustion engine is, for example, detected in the form of revolution angular acceleration or revolution angular acceleration deviation of the engine. The detected quantity of revolution fluctuation is compared with a threshold value in the currently chosen fuel injection mode. Thus, deterioration of combustion is surely judged according to each fuel injection mode. In particular, threshold values in a compression stroke injection mode are determined to be larger than threshold values in an intake stroke injection mode.

Abstract: In an intra-cylinder injection type engine, a first fuel cut-off starting rotational speed, a first return rotational speed and a first target idling speed in a compression stroke injection mode, which is superior in both combustion and responsivity, are set at lower speeds than a second fuel cut-off starting rotational speed, a second return rotational speed, and a second target idling speed in a suction stroke injection mode. During an operation in the compression stroke injection mode, a fuel cut-off mode and an idle running of the engine are practiced at a low engine speed, to improve the fuel economy without causing deterioration of combustion.

Abstract: A lean-burn internal combustion engine capable of stably securing a satisfactory vacuum for a vacuum actuator which uses a vacuum in an intake manifold disposed on the side downstream of an intake air amount control mechanism, while preventing a deterioration of a specific fuel consumption and a drivability of the engine. A filling state of gases in the intake manifold is controlled based on pieces of information in respect of an engine operating state and a reduction in vacuum, whereby a vacuum such as to ensure the operation of the vacuum actuator is secured. A control for inhibiting a lean-burn operation of the engine and for suppressing an EGR amount or inhibiting the EGR is made in accordance with an braking manipulation, the ON/OFF state of a vacuum switch, or an output from a vacuum sensor at the time of lean-burn operation.

Abstract: When starting of an in-cylinder injection engine 1 is detected, a cylinder discrimination, which discriminates each cylinder, is effected. After each cylinder is discriminated, it is determined whether or not a water temperature detected by a water temperature sensor 16 exceeds a predetermined value. When the water temperature is below the predetermined value, fuel injection is started from the fuel injection valve 4 of a cylinder subjected to at least one compression stroke. Thereby, the cylinder discrimination is effected quickly, and it is made possible to raise the temperature within the combustion chamber 5, by means lapse of at least one compression stroke, at low water temperatures at which the starting ability tends to be deteriorated, and the starting ability of the in-cylinder injection engine 1 at low water temperatures is improved while shortening the starting time.