Abstract: A digital camera maintains a consistent effective focal length upon switching from a first focus mode to a second focus mode, the focus modes having different maximum focal lengths. Maintaining a consistent effective focal length across focus mode changes obviates the need for a user to reframe a scene upon changing focus modes.

Abstract: Producing calibration data (to remove vignetting, e.g., color-dependent vignetting) for a digital camera includes: arranging, in front of the camera, a white reference surface that is to be imaged; capturing, via the camera, a characteristic array of data corresponding to an image of the reference surface for each color that the camera can image; and manipulating each characteristic array to reduce a total amount of data representing the reference image.

Abstract: A method of controlling a zoom lens includes zooming to a desired focal length in one of two directions, and determining a focus lens position at least partly from the desired focal length based upon said one of said two directions.

Abstract: A method and apparatus for compensating for the presence of artificial illumination in a scene when auto-focusing a lens is disclosed.

Abstract: A method and apparatus is disclosed for auto-exposure control in a scene under artificial illumination that synchronizes the exposure control algorithm and final image capture with the intensity variations in the artificial illumination.

Abstract: A method and apparatus for color correcting for the presence, in a scene, of artificial illumination that is powered by alternating current is disclosed. By sampling the light in a scene at a periodic rate the presence of artificial illumination can be detected and then color corrected.

Abstract: A method and apparatus for detecting the presence of artificial illumination in a scene powered by alternating current by sampling the light in a scene at a periodic rate.

Abstract: A method and device for improving the generation of the focus signal in the auto-focus system of a camera.

Abstract: A fuel admission valve for metering gas without using a mass flow sensor. The valve uses a flow control element and nozzle, an actuator, a fuel supply pressure sensor, a fuel supply temperature sensor, a flow control element position sensor, and a flow control circuit to meter gas in sonic flow with insensitivity to the discharge pressure.

Abstract: A gas fuel admission system for use with a gas fuel supply and an internal combustion engine having an engine control unit that produces a desired mass flow signal. The system has a continuously variable gas fuel admission valve having a flow control element and nozzle for metering gas in sonic flow from the gas supply to the engine with insensitivity to the valve discharge pressure. An actuator moves the flow control element relative to the nozzle. The system also has a flow control circuit that responds to the desired mass flow signal from the engine control unit, a gas supply pressure signal from a gas supply pressure sensor, a gas supply temperature signal from a gas supply temperature sensor, and a flow control element position signal from a flow control element position sensor to determine the appropriate flow control element position needed to achieve the desired mass flow at the present engine operating conditions.