445 results about "Anode voltage" patented technology

An electron-emitting cathode consists of an electrically conducting emitter layer attached to a side wall which consists of stainless steel and a gate which is fixed at a mall distance inside a concave emitter surface of the emitter layer. The cathode surrounds a reaction area containing a cylindrical grid-like anode and a central ion collector which consists of a straight axial filament. An ion collector current reflecting the density of the gas in the reaction region is measured by a current meter while a gate voltage is kept between the ground voltage of the emitter layer and a higher anode voltage and is regulated in such a way that an anode current is kept constant. The emitter layer may consists of carbon nanotubes, diamond-like carbon, a metal or a mixture of metals or a semiconductor material, e.g., silicon which may be coated, e.g., with carbide or molybdenum. The emitter surface can, however, also be a portion of the inside surface of the side wall roughened by, e.g., chemical etching. The gate may be a grid or it may be made up of patches of metal film covering spacers distributed over the emitter area or a metal film covering an electron permeable layer placed on the emitter surface.

A fully differential sensing apparatus and an input common mode feedback circuit are provided. The input common mode feedback circuit includes a common mode error amplifier and a plurality of adaptive conductance elements. Each adaptive conductance element behaves with a low impedance characteristic when its anode voltage is greater than its cathode voltage by a positive threshold voltage or, on the contrary, when the anode voltage of such an adaptive conductance element is lower than its cathode voltage by a negative threshold voltage, the adaptive element also behaves with a low impedance characteristic; otherwise the aforementioned adaptive conductance element behaves with a high impedance characteristic. The common mode error amplifier and a plurality of such adaptive conductance elements form a negative feedback loop to effectively maintain the input common voltage of a fully differential input amplifier, which can be used for a fully differential sensing apparatus.

The invention provides an organic light emitting diode pixel circuit integrated with an external processor and a driving method thereof, which can eliminate influences caused by transistor threshold voltage variation. However, due to influences of factors such as internal parasitic parameters of the transistor, the threshold voltage variation is not always completely counteracted, and thus, through the external processor, in a light emitting stage, sensing and compensation value calculation are carried out for anode voltage of the organic light emitting diode, the originally-outputted data voltage is adjusted through the compensation value, and influences of uneven brightness caused by threshold voltage variation and organic light emitting diode deterioration are improved.

The invention provides a system for sensing the pixel driving characteristic of an AMOLED (Active Matrix Organic Light Emitting Diode) and an AMOLED display device. The anode voltage of an organic light emitting diode (OLED) in a pixel driving circuit (10) and the output voltage of a variable negative voltage source (21) are connected to a voltage summing circuit (22) at a sensing phase, and the voltage summing circuit (22) inputs the summing result to an analog to digital converter (ADC) (23). The variable negative voltage source (21) is adjusted according to the change of the anode voltage of the OLED, and the input voltage of the ADC (23) can be adjusted under the co-action of the variable negative voltage source (21) and the voltage summing circuit (22) and then is within a sensing range of the ADC (23) all the time, so that the anode voltage of the OLED is accurately measured, the pixel driving characteristic of the AMOLED is ensured, then the compensation effect on data signals is ensured, and the image quality of the AMOLED display device is improved.