Patents
Literature
Patsnap Copilot is an intelligent assistant for R&D personnel, combined with Patent DNA, to facilitate innovative research.
Patsnap Copilot

812results about How to "Light evenly" patented technology

Self-excited oscillation type high power LED constant-current driving circuit

The invention provides a self-oscillation type high power LED constant-current drive circuit with low cost, high reliability and stability and high drive efficiency, the circuit comprises a rectifier and filter circuit, a switching circuit, a steady voltage constant current output circuit, a transformer, a self-oscillation type pulse width modulation signals generating circuit and a current feedback obstruction circuit, wherein the rectifier and filter circuit accesses commercial power into rectification, changes the commercial power into direct current, and then outputs commercial power to the switching circuit to switch in a self-oscillation type with high frequency, then high frequency voltage of the steady voltage constant current output circuit is transformed into direct voltage through the transformer to drive the LED, simultaneously sampling current signals produces jam signals through the current feedback obstruction circuit to control the switching circuit to work, the circuit does not adopt any driving chips and only uses fewer common individual devices to form a self-oscillation type structure to drive the switching circuit and to combine current feedbacks, which realizes constant current driving of the high power LED.
Owner:NANTONG LIWANG MACHINE TOOL +1

Method for detecting appearance of semiconductor chip

The invention discloses a method for detecting appearance of a semiconductor chip. The device comprises a sucking mechanism, a U-shaped reflecting plate, two light sources, plane reflecting mirrors, a lens, a camera and an adjusting mechanism, wherein the sucking mechanism is used for sucking a chip to be detected to a position to be detected; the U-shaped reflecting plate is arranged on the sucking mechanism; the two light sources are symmetrically arranged on the side of the chip; one part of light emitted by the two light sources irradiates the U-shaped reflecting plate and performs backlight illumination on the bottom surface and one group of opposite sides of the chip, and the other part of light performs backlight illumination on the other group of opposite sides of the chip; a plurality of plane reflecting mirrors are obliquely and symmetrically arranged at the periphery below the chip, so that light rays reflected by the plane reflecting mirrors are vertically transmitted to the front end face of the lens; the lens is arranged on the camera and positioned below the chip; the camera is arranged on the adjusting mechanism; and the adjusting mechanism is used for adjusting the working distance of the camera. By a backlight illumination technology, a device is clearly imaged, contrast is high, lighting uniformity is achieved, detection time is shortened, and efficiency is improved.
Owner:HUAZHONG UNIV OF SCI & TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products