4results about How to "Increase the pulse width" patented technology

The invention discloses an active and passive mode locking combined femtosecond disc laser, and belongs to the field of disc laser. The femtosecond disc laser comprises a pumping source, a pumping cavity, a disc laser crystal and a resonant cavity, pumping laser emitted by the pumping source is reflected for multiple times in the pumping cavity and passes through the disc laser crystal for multiple times to generate oscillation laser; the resonant cavity comprises a first branch and a second branch, the first branch comprises a dispersion mirror group, a hard diaphragm and an output mirror which are sequentially arranged along a light path, and the second branch comprises a first concave mirror, a second concave mirror, a first high-reflection mirror, a third concave mirror, an acousto-optic modulator and a second high-reflection mirror which are sequentially arranged along the light path; the acousto-optic modulator is located at the focal point of the third concave mirror, and modulates periodic loss and starts passive mode locking in the active mode locking process; oscillation laser generates a femtosecond laser pulse sequence after passing through the acousto-optic modulator, the femtosecond laser pulse sequence is reflected to return to the disc laser crystal along the original path and enters the first branch, and the femtosecond laser pulse sequence is output through the output mirror.

According to one aspect of this disclosure, a display device includes: a timing controller configured to generate image data, a data control signal, and a gate control signal, the gate control signal including a cutoff clock signal; a data driver configured to generate a plurality of data signals corresponding to the image data based on the data control signal, and output the data signals to a plurality of data lines; a gate driver configured to generate a plurality of gate signals based on the gate control signal, and output the gate signals to a plurality of gate lines; and a display panel including a plurality of pixels disposed in a display area and connected to the plurality of data lines and the plurality of gate lines. The timing controller stops the transmission of image data during a period when a low-power drive signal is at a logic high level, and the gate driver changes the pulse width of a gate signal among the plurality of gate signals that has a conduction level pulse overlapping with the period when the low-power drive signal is at a logic high level.

A dispersion measurement device includes a pulse forming unit, an optical detection unit, and an arithmetic operation unit. The pulse forming unit includes an SLM that presents a phase pattern giving a predetermined phase shift for each of wavelength to the first optical pulse, and forms an optical pulse train from the first optical pulse, the optical pulse train including a plurality of second optical pulses having a time difference from each other and having center wavelengths different from each other. The optical detection unit detects a temporal waveform of the optical pulse train. The arithmetic operation unit is electrically connected to the optical detection unit. An optical component is arranged on an optical path between the pulse forming unit and the optical detection unit. The arithmetic operation unit estimates a wavelength dispersion amount of the optical component based on a feature amount of the temporal waveform. The phase pattern of the SLM includes a pattern for giving a group delay dispersion having a sign opposite to the group delay dispersion of the optical component to the first optical pulse.

The invention relates to an open-loop control or closed-loop control device for open-loop control or closed-loop control of a light-emitting diode field having n light-emitting diodes, the device having an output end, by means of which an open-loop control or closed-loop control signal for open-loop control or closed-loop control of a controllable switching element can be intercepted, the open-loop control or closed-loop control device can define the switch-on time and / or switch-off time of a pulse by means of the open-loop control signal or the closed-loop control signal, and can control one and / or more controllable switching elements to be closed or open during the determined pulse, k groups are determined or can be determined, each LED is assigned to one of the k groups, so that each of the k groups contains m j light emitting diodes, where 1≤j≤k and I(FI)#imgabs0# and the determined switch-on time and / or switch-off time of the pulses of each group are determined by an open-loop control or closed-loop control device so that the pulses overlap as little as possible.