摘要:
A dustproofing mechanism for a thin, disc film cartridge type camera having windows in its front wall for the camera viewfinder and objective lens includes a cover structure guided for movement to alternative positions opening or closing both windows and an operating member accessible through one of the windows is connected to the cover structure to permit the manual selective movement of the cover structure to the window open or closed position.
摘要:
According to one embodiment, a time difference amplifier circuit includes the first amplifier including first positive and negative inputs and first positive and negative outputs, the second amplifier including second positive and negative inputs and second positive and negative outputs, first to fourth wirings, a selection circuit including the first selection element connecting the first or fourth wirings to the second positive input, and the second selection element connecting the second or third wirings to the second negative input, and a control circuit connecting the amplifiers by the first and second wirings or by the third and fourth wirings.
摘要:
A conventional DC/DC converter with both a step-up function and a step-down function has a drawback that its output voltage will be discontinuous when its operations are switched. An error signal, which is representative of a difference between a target voltage and a present voltage, is inputted to both a step-down switching control circuit and a step-up switching control circuit. When the difference between the target voltage and the present voltage is below a predetermined value, the switching of the step-down and step-up converters by the step-down and step-up switching control circuits, respectively, are caused to concurrently run in a time division manner.
摘要:
Provided is an AD converting apparatus that converts an analog input signal into a digital output signal, comprising a plurality of AD converters supplied with sampling clocks differing from each other by prescribed phase amounts, each AD converter outputting an individual signal obtained by digitizing the input signal according to the supplied sampling clock; a plurality of amplitude-dependent characteristic correcting sections that are provided to correspond to the plurality of AD converters, each amplitude-dependent characteristic correcting section generating a corrected individual signal by correcting the individual signal output by the corresponding AD converter using a correction factor corresponding to an amplitude of the individual signal; and a combining section that generates the output signal by combining a plurality of the corrected individual signals.
摘要:
A continuous-time band-pass ΔΣ AD modulator subtracts an analog signal from a DA converter from an inputted analog signal, outputs an analog signal having a subtraction result to an AD converter via a continuous-time analog band-pass filter, outputs a digital signal from the AD converter to the DA converter, and outputs the same digital signal as a digital signal subjected to a band-pass ΔΣ AD modulation processing. The highest input frequency “fin” of the inputted analog signal is substantially set to three-fourths of a sampling frequency “fs”. The DA converter is configured to convert the inputted digital signal into the analog signal, and outputs the analog signal, which is inverted or not in response to a value of the inputted digital signal and has an amplitude of substantially zero and a gradient of substantially zero at a timing k/(2fs).
摘要:
A DA converter circuit is provided for use in a ΔΣ AD modulator. The DA converter circuit includes a DA converter of segment switched capacitor type. The DA converter includes an operational amplifier, capacitors as connected in parallel to each other to supply electric charges to the operational amplifier, an electrically charging switch for switching of electrically charging electric charges onto the respective capacitors or not, and an electrically discharging switch for switching or not electrically discharging electric charges from the respective capacitors or not. A switch device performs either one of the electrically charging, the electrically discharging, grounding, and polarity inversion onto the respective capacitors. A controller controls the electrically charging switch, the electrically discharging switch and the switch device to execute a process of second-order DWA algorithm for performing a second-order noise shaping of a non-linearity of the DA converter circuit.
摘要:
A camera having a photographic optical system, a lens barrel disposed to be movable relative to a camera body in a direction of an optical axis and holding the photographic optical system, a focal length switchover mechanism for moving the photographic optical system such that the photographic optical system has a longer focal length as the same is moved forwardly in the direction of the optical axis, and a lens barrier displaceable between a closed position and an opened position for covering and uncovering a front face of the lens barrel. This lens barrier is disposed independently of the lens barrel adjacent a front end of the lens barrel having returned to a home position thereof at the side of the camera body such that the lens barrier is not movable in unison with the lens barrel. The lens barrel is moved to a projected position at which a front portion of the same is projected forwardly of the lens barrier when the focal length of the photographic optical system is set to be long by the focal length switchover mechanism. When the lens barrel is placed at the projected position and if the lens barrier is operated to its closed position, the lens barrel first returns to its home position before the lens barrier will close.
摘要:
A camera having at least two objective lenses of different focal lengths, which can be selectively externally manually positioned in the camera photographic optical path includes an inverted Galilean viewfinder optical system consisting of a front negative, divergent lens group and a rear positive, convergent lens group. The divergent lens group consists of two concave lenses which are transferrable between a first position providing a low magnification and a second position providing a high magnification. In the first position both concave lenses are in the viewfinder optical path and the other concave lens remains in the viewfinder optical path and is shifted to a second position axially spaced from its first position along the finder optical axis.
摘要:
To provide a complex bandpass ΔΣAD modulator capable of suppressing the influence of an image component caused by a mismatch between I- and Q-channels on a signal component with low power consumption.A complex bandpass ΔΣAD modulator 10 is configured by a subtraction unit 20, a complex bandpass filter 30, an addition unit 40, a noise extraction circuit unit 50, an ADC unit 60, and a DAC unit 70. The noise extraction circuit unit 50 extracts a quantized noise signal of the ADC unit 60 based on an input signal of the ADC unit 60 and an output signal of the DAC unit 70, delays the extracted quantized noise signal by one sample time, phase-rotates the delayed signal by a predetermined angle, and feeds back the rotated signal to the input side of the ADC unit 60. Thus, a complex bandpass ΔΣAD modulator capable of suppressing the influence of the image component caused by a mismatch between I- and Q-channels on the signal component with low power consumption is provided.