Patent Application
20250148959
The present invention generally relates to a display system, and more particularly to a display system and method with electromagnetic susceptibility (EMS).
A portable computer such as laptop computer or notebook computer is a small, portable personal computer (PC). Portable computers typically have a flat panel screen (e.g., liquid-crystal display (LCD) panel) on the inside of the upper lid and an alphanumeric keyboard and pointing device (such as a trackpad and/or trackpoint) on the inside of the lower lid.
Electromagnetic interference (EMI) is unwanted noise or interference in an electrical path or circuit caused by an outside source such as a mobile phone. It can cause electronics to operate poorly, malfunction or stop working completely. Portable computers are not immune to EMI and can be affected by it.
Water ripple phenomenon and V-band effect are caused by EMI on the gamma voltage (as a reference voltage) for the LCD panel, thereby affecting gray scale display and color white balance of the LCD panel.
A need has arisen to propose a novel scheme for resisting EMI, particularly to prevent or mitigate (water) ripple phenomenon or V-band effect caused by EMI.
In view of the foregoing, it is an object of the embodiment of the present invention to provide a display system and method with electromagnetic susceptibility (EMS) capable of functioning properly in the presence of electromagnetic interference (EMI) and effectively preventing or mitigating (water) ripple phenomenon or V-band effect caused by EMI.
According to one embodiment, a display system with electromagnetic susceptibility includes a programmable gamma circuit, a timing controller and a source driver. The programmable gamma circuit is capable of being adjusted dynamically to supply a programmable gamma voltage curve that provides gamma voltage. The timing controller receives image data and converts format of the received image data, thereby generating data signal. The source driver receives the data signal from the timing controller and the gamma voltage from the programmable gamma circuit. The source driver sends a notification signal to the timing controller indicating that the data signal is not properly received, and the timing controller then programs the programmable gamma circuit to provide an offset voltage level to binding points of the programmable gamma circuit for a predetermined time period.
According to another embodiment, a display method with electromagnetic susceptibility includes the following steps: determining whether electromagnetic interference (EMI) is present; a source driver sending a notification signal to a timing controller if the EMI is present; and the timing controller programming a programmable gamma circuit to provide an offset voltage level to binding points of the programmable gamma circuit for a predetermined time period in response to the notification signal.
In the embodiment, the display system 100 may include a liquid-crystal display (LCD) panel 11 composed of liquid crystals that may be electronically modulated to pass or block light. The display system 100 may include a programmable gamma circuit 12 (e.g., an integrated circuit) disposed on a substrate 10 (e.g., printed circuit board or PCB) and configured to supply a programmable gamma voltage curve that provides gamma voltage (as a reference voltage), thereby affecting gray scale display and color white balance of the LCD panel 11. The gamma voltage curve is not a linear curve because human eye's perception of light is not linear. The programmable gamma circuit 12 of the embodiment supplies a gamma voltage curve with grayscale capable of being adjusted dynamically to make the display screen of the LCD panel 11 more in line with human eye's perception of light.
The portable computer 100 of the embodiment may include a timing controller (Tcon) 13, for example, an integrated circuit, disposed on the substrate 10 (e.g., PCB) and configured to receive image data and to convert format of the received image data, thereby generating (image) data signal. The timing controller 13 of the embodiment may include a communication interface 131, such as a serial communication interface (e.g., inter-integrated circuit or I2C interface) adaptable to programming the programmable gamma circuit 12.
The portable computer 100 of the embodiment may include a source driver (SD) 14 disposed on the substrate 10 (e.g., PCB) and configured to receive the data signal (from the timing controller 13) which is then displayed on the LCD panel 11 and to receive the gamma voltage (from the programmable gamma circuit 12).
Referring to
If it is determined that EMI is present, the source driver 14 then sends a notification (or feedback) signal (to the timing controller 13) indicating that the data signal is not properly received (step 22); otherwise the flow goes back to step 21. In one embodiment, the source driver 14 may include a clock and data recovery (CDR) circuit 141 configured to generate the notification signal. It is noted that the EMI may also cause an unlock phenomenon between the timing controller 13 and the source driver 14.
Subsequently, in step 23, in response to the notification signal, the timing controller 13 increases amplitude of the data signal, which is then resent to the source driver 14. According to one aspect of the embodiment, in step 24, the timing controller 13 programs the programmable gamma circuit 12 via the communication interface 131 (e.g., I2C). Specifically, the timing controller 13 outputs a code to the programmable gamma circuit 12 via the communication interface 131, thereby providing an offset voltage level (e.g., 1 volt) to the binding points of the programmable gamma circuit 12 (e.g., V12, V7, HAVDDIN, V6 and V1 as exemplified in
In step 25, an (internal) counter (of the timing controller 13) counts until the counter reaches a predetermined time period (e.g., in a range of 30 seconds to 1 minutes), at that time the flow goes back to step 21 for normal operation.
According to the embodiment as described above, particular the execution of step 24, (water) ripple phenomenon or V-band effect caused by EMI can be effectively prevented or mitigated.
Although specific embodiments have been illustrated and described, it will be appreciated by those skilled in the art that various modifications may be made without departing from the scope of the present invention, which is intended to be limited solely by the appended claims.
