2830results about How to "Reduce jitter" patented technology

A virtual computer monitor is described which enables instantaneous and intuitive visual access to large amounts of visual data by providing the user with a large display projected virtually in front of the user. The user wears a head-mounted display containing a head-tracker, which together allow the user to position an instantaneous viewport provided by the head-mounted display at any position within the large virtual display by turning to look in the desired direction. The instantaneous viewport further includes a mouse pointer, which may be positioned by turning the user's head, and which may be further positioned using a mouse or analogous control device. A particular advantage of the virtual computer monitor is intuitive access to enlarged computer output for visually-impaired individuals.

A clock control circuit which includes a frequency multiplying interpolator for generating and outputting multiphase clocks by frequency multiplying an input clock; a switch for outputting two of the multiphase clocks input thereto from the frequency multiplying interpolator; a fine adjusting interpolator, to which the two outputs from the switch are applied, for outputting a signal obtained by internally dividing the phase difference between the two outputs; and a control circuit for controlling the switching of the switch and varying the internal-division ratio of the fine adjusting interpolator.

A DLL for reducing jitter during a high frequency operation by separately controlling a coarse delay and a fine delay. The DLL includes a multiplexing unit for selectively outputting one of the rising clock and the falling clock; a first delay line for generating a first internal clock and a second internal clock; a second delay line for generating a first clock and a second clock; a delay line control unit for controlling the second delay line; a phase control unit for generating a first DLL clock and a second DLL clock by mixing the first clock and the second clock; and a phase comparing unit for comparing the first DLL clock and the second DLL clock with the rising clock to generate a lock signal for controlling an operation timing of the first delay line and the second delay line.

A clock recovery circuit for recovering clock signals from one of a plurality of input reference signals, includes an acquisition phase locked loop (PLL) for each input. The acquisition PLL having phase comparator for comparing the phase of an input signal to a feedback signal, and first and second digital controlled oscillators (DCOs) receiving an input from the phase comparator. The first DCO of the acquisition PLL is in a feedback loop to supply an input to the phase comparator and the second DCO of the acquisition PLL has a control input to introduce a phase offset therein relative to said the DCO of the acquisition PLL and provides an output for the acquisition PLL. An output PLL has a phase comparator selectively connectable to the output of each of the acquisition PLLs. The output PLL has a first DCO providing an output for the circuit and a second DCO in a feedback loop providing a feedback signal to the phase comparator of the output PLL. The second DCO of the output PLL has a control input to introduce a phase offset therein relative to the first DCO of the output PLL. A control unit for sets the phase of the second DCO of the acquisition circuit and the second DCO of the output PLL to a common value during changeover from one input to another to avoid an instantaneous phase error upon switching reference signals.