Circuitry for independent gamma adjustment points

An integrated circuit, comprising:

• an input bus for receiving an image data stream having image data corresponding to a plurality of color channels;
• and
• a gamma processing block comprising:
• gamma adjustment circuitry comprising:
• a resistor string defining a plurality of voltage level outputs;
• a switching matrix comprising a first set of conductors coupled to each of the voltage level outputs from the resistor string, a second set of conductors coupled to each of a plurality of gamma adjustment voltage taps, and a plurality of switches comprising a switch located at each intersection of a conductor from the first set and a conductor from the second set, wherein each switch, when operating in a closed state, is configured to couple a gamma adjustment voltage corresponding to the wire from the second set to a voltage level output of the resistor string output coupled to the wire from the first set;
• and
• a selection circuit configured to receive and select one of the voltage level outputs from the resistor string based upon a selection signal comprising a digital level representation of the image data being processed and to output the selected voltage level output from the gamma processing block;
• gamma control logic comprising:
• a memory configured to store a gamma correction profile for each color channel, wherein each gamma correction profile defines a set of switches within the switching matrix corresponding to desired gamma adjustment locations for its respective color channel, the desired gamma adjustment points being determined based at least in part on a range of voltages that corresponds to a range of maximum values along a transmittance sensitivity curve for each respective color channel, wherein the desired gamma adjustment points are substantially optimized to concentrate a portion of the gamma adjustment points in the range of maximum values along the transmittance sensitivity curve for each respective color channel;
• time division logic configured to implement a time division multiplexing scheme in which image data corresponding to each of the color channels is selected and processed in consecutive discrete timeslots, wherein during each timeslot, gamma adjustment points corresponding to a selected color channel are determined by selecting one or more switches within the switching matrix based upon the gamma correction profile associated with the selected color channel, wherein the discrete timeslots repeat in an alternating manner.

A method for manufacturing a display device, comprising:

• providing a display panel having a plurality of unit pixels arranged in columns and rows defined by source lines and gate lines, respectively, wherein each unit pixel is coupled to an intersection of a source line and a gate line, and wherein the display panel comprises a plurality of color channels;
• coupling a source driver integrated circuit (IC) to the display panel, wherein the source driver IC is configured to receive image data corresponding to each of the plurality of color channels and to drive the display panel for displaying images, the source driver IC comprising:
• gamma control logic configured to store a gamma correction profile for each of the plurality of color channels;
• gamma adjustment circuitry configured to select for each color channel, a respective set of gamma adjustment points for providing a respective set of gamma adjustment voltages to a digital-to-analog converter configured to provide a plurality of output voltage levels, wherein the selection of the respective set of gamma adjustment points is based upon a respective gamma correction profile for a corresponding color channel;
• and
• a selection circuit configured to select one of the output voltage levels based upon a selection signal;
• wherein each respective gamma correction profile defines a respective one of a set of gamma adjustment points determined based upon transmittance sensitivity characteristics associated with a transmittance versus voltage curve of a respective color channel, wherein the respective one of the set of gamma adjustment points is configured to substantially optimize a portion of respective one of the set of gamma adjustment points to concentrate in a voltage range that corresponds to an area comprising a maximum absolute value of the transmittance sensitivity characteristics of the respective color channel;
• and
• coupling a gate driver IC to the display panel, wherein the gate driver IC is configured to sequentially activate rows of unit pixels based upon timing signals provided by the source driver IC.

A method, comprising:

• providing a gamma correction profile for each of a plurality of color channels in a display device;
• applying a respective gamma correction profile to a gamma adjustment circuit associated with each color channel, wherein the gamma correction profile for each color channel comprises data representative of locations of gamma adjustment points to be applied to a particular color channel to compensate for gamma inaccuracies of the display device, wherein the locations of the gamma adjustment points are determined by substantially optimizing a portion of the gamma adjustment points to concentrate in a voltage range that corresponds to the maximum transmittance sensitivity characteristics of the particular color channel;
• applying for each gamma adjustment circuit a respective set of gamma adjustment voltages to respective gamma adjustment points corresponding to a respective applied gamma correction profile;
• providing from each gamma adjustment circuit a plurality of adjusted voltage outputs, the voltage outputs having been adjusted based upon the respectively applied set of gamma adjustment voltages;
• selecting one of the plurality of voltage outputs using a selection circuit;
• and
• outputting the selected voltage output to a display panel.

One or more non-transitory tangible computer-readable storage media comprising a computer program product, the computer program product comprising:

• code to determine a maximum and minimum voltage value at which to apply gamma adjustment voltages for a color channel of a display device based at least partially upon a transmittance sensitivity curve for the color channel and a desired white balance and to select gamma adjustment points corresponding to each of the determined maximum and minimum voltage values, wherein the transmittance sensitivity curve is determined based at least in part on a transmittance versus voltage curve for the channel;
• code to determine a first voltage range corresponding to a region over which the color channel exhibits a highest degree of sensitivity and to select one or more gamma adjustment points along a resistor string that corresponds to the color channel such that the resistor string outputs a plurality of voltages generally distributed within the first voltage range, wherein the code to select the one or more gamma adjustment points comprises substantially optimizing a portion of the one or more gamma adjustment points to concentrate in the first voltage range;
• and
• code to store the selected gamma adjustment points as a gamma correction profile.