2726results about How to "Small distortion" patented technology

A meniscus combiner for a head up display (HUD) system. The meniscus combiner includes a meniscus lens; a multi-layer dichroic coating formed on a first surface of the meniscus lens; and, an anti-reflection coating formed on a second, opposite surface of the meniscus lens. The meniscus combiner preferably utilizes a non-symmetric aspheric meniscus lens which simplifies the optical system of the image source (overhead or in-dash unit) minimizing aberrations and minimizing costs. The meniscus combiner may be fabricated utilizing a number of lens sections which may be bonded together and blended. Use of multiple lens sections provides the ability to easily optimize the lens design. Alternatively, the meniscus combiner can be fabricated from a single lens.

The invention relates to a super wide angle mega pixel vehicle-mounted lens, comprising two lens groups and diaphragm, wherein, starting from an object space, a front lens group with negative focal power, the diaphragm and a rear lens group with positive focal power are sequentially arranged. The front lens group comprises a first and a second lenses with negative focal power and a third lens with positive focal power; and the rear lens group comprises a glued lens plate group and a sixth lens with positive focal power. The second and the sixth lenses are aspherical lens plates, and at least one face includes an aspherical mirror face. The invention can realize super wide angle, large relative aperture and low distortion, still have high light permeability and definition in the temperature range from minus 40 DEG C to plus 85 DEG C, and is especially suitable for outdoor monitoring and a vehicle-mounted camera system under adverse environment.

A coding method of frequency hand expansion includes copying special frequency band of low frequency excited chart to special frequency hand of high frequency (HR) to obtain HR copied-excited chart, obtaining original HR excited chart according to certain signal, regulating HR copied-excited chart to obtain regulated HR copied-excite chart, making IDFT conversion on said chart to obtain HR copied-excited signal, filtering said signal to obtain rebuilt HR time domain signal, picking up gain regulation parameter of time domain and outputting HR parameter. The device used for realizing said method is also disclosed.

A power amplifier (1) for receiving and amplifying an input signal (10) and outputting an output signal (11) is disclosed. The power amplifier comprises: N power amplifying units (12) (N is an integer larger than 1) connected in parallel so as to output amplified signals in response to the input signal (10); an output combining unit (14) for combining the output signals from the N power amplifying units (12) and outputting a combined signal as the output signal (11) of the power amplifier; and an amplitude controlling unit (15) for selectively turning ON each of the N power amplifying units (12) based on an amplitude of the input signal (10). In the power amplifier, the amplitude controlling unit (15) may comprise N amplitude adjusters (113) connected in parallel for adjusting the amplitude of the input signal (110) of the power amplifier; and a controller (115) for selectively turning ON each of the N power amplifying units (112) and controlling the amplitude adjusters (113) so that an amplitude of the output signal (111) becomes a substantially continuous function with respect to the amplitude of the input signal (110). The power amplifier may further comprise a local oscillator (222) outputting an constant envelope signal, receiving a modulation signal (210) as the input signal of the power amplifier and outputting an amplified modulated signal (211) as the output signal of the power amplifier; wherein the N power amplifying units comprise N saturation amplifying units connected in parallel so as to amplify the constant envelope signal from the local oscillator; and the amplitude controlling unit comprises an amplifying controller (215) for selectively turning ON each of the N saturation amplifying units (212) based on an amplitude of the modulation signal (210).

The invention discloses a speech enhancement method for speech recognition in a noise environment, and the method comprises the steps: combining the improved MVDR beam forming which is based on the time-frequency masking and employs the speech time-frequency domain sparsity principle with the improved Wiener filtering, acquiring a speech signal of a microphone array, and constructing an MVDR beamformer based on time-frequency masking, making full use of the spatial information of the speech signal, enhancing the speech signal in a target direction, suppressing the interference of noise in other directions, and then removing the residual noise and improving the speech intelligibility through a modified Wiener filter. The method is applied to a voice recognition front end, and can effectively remove noise and improve the voice intelligibility, thereby improving the recognition rate of a speech recognition system, solving a problem of how to reduce the speech distortion in the noise environment and improve the speech recognition rate of the noise environment. The method can be applied to a household robot and intelligent voice equipment.