High speed image refresh system
A LED controller for an LED pixel array includes an image frame buffer to receive image data and a standby image buffer connected to the image frame buffer to hold a standby image. A command and control module connected is configured to substitute the standby image in the standby image buffer for the image in the image frame buffer when image data is unavailable.
1. A method of fabricating an illumination device, the method comprising:
coupling a light emitting diode (LED) array with a driver;
coupling the driver with an image frame buffer configured to store data to control driving of the LED array by the driver;
coupling the image frame buffer with a standby image frame buffer configured to store standby vehicle image data; and
coupling a processor to the frame buffer, the processor configured to use instructions to:
determine whether valid vehicle image data is present in the image frame buffer; and
in response to determining that valid vehicle image data is not present in the image frame buffer, control the image frame buffer to load the standby vehicle image data and control the driver to drive the LED array using the standby vehicle image data to generate an image.
2. The method of claim 1 , further comprising selecting the standby image data from among a plurality of sets of standby vehicle image data stored in the standby image buffer.
3. The method of claim 1 , wherein determining whether valid image data is present in the image frame buffer comprises determining whether at least one error is present in the vehicle image data.
4. The method of claim 1 , wherein the valid vehicle image data corresponds to an image having an intensity and spatial pattern consistent with a headlamp radiation pattern of the vehicle.
5. The method of claim 4 , wherein the standby vehicle image data corresponds to an image having an intensity and spatial pattern consistent with a legally allowed low beam headlamp radiation pattern of the vehicle.
6. The method of claim 1 , wherein the instructions further configure the processor to:
determine whether sensor signals have been received from the vehicle, the sensor signals selected from a set of sensor signals that include environmental conditions, vehicle conditions, and presence and location of other vehicles and pedestrians proximate to the vehicle; and
adjust the vehicle image data based on the sensor signals to generate the image.
7. The method of claim 1 , wherein the instructions further configure the processor to determine whether valid vehicle image data is present in the image frame buffer by determining whether valid vehicle image data has been received at the image frame buffer via an interface to at least one peripheral component of a vehicle.
8. The method of claim 7 , wherein the instructions further configure the processor to:
determine whether valid vehicle image data has been received at the image frame buffer by determining whether valid vehicle image data has been received for a set of multiple image frames to display a particular image for each of the set of multiple image frames, and
in response to determining that valid image data has been received at the image frame buffer for the multiple frames, repeat driving the LED array using the image data for another set of multiple image frames.
9. The method of claim 1 , wherein the instructions further configure the processor to control the driver to set ramp times and pulse width to drive each LED pixel to generate the image.
10. The method of claim 1 , wherein the instructions further configure the processor to:
control groups of pixels of the LED array as individual blocks; and
partially refresh the image data in the image frame buffer to alter the image by only the groups of pixels associated with the partially refreshed image data.
11. A compound metal oxide semiconductor (CMOS) backplane comprising:
a driver configured to drive a light emitting diode (LED) array attached thereto to generate an image from a vehicle based on image data supplied thereto;
an image frame buffer;
a standby image buffer coupled to the image frame buffer, the standby image buffer configured to hold sets of standby image data;
a controller coupled to the image frame buffer and the standby image buffer, the controller configured to select one set of the standby image data for transmission to the driver to generate an image by the LED array in response to a determination that the image frame buffer does not contain valid image data to supply to the driver; and
at least one filter configured to provide filtered power to components of the CMOS backplane.
12. The CMOS backplane of claim 11 , wherein the at least one filter is configured to provide at least power protection selected from a set of power protections that include electrostatic discharge (ESD) protection, load-dump protection, alternator field decay protection, and reverse polarity protection.
13. The CMOS backplane of claim 11 , wherein the valid image data and the standby image data each corresponds to an image having an intensity and spatial pattern consistent with a headlamp radiation pattern of a vehicle.
14. The CMOS backplane of claim 11 , wherein the standby image data corresponds to an image having an intensity and spatial pattern consistent with a legally allowed low beam headlamp radiation pattern of the vehicle.
15. The CMOS backplane of claim 11 , wherein the controller is further configured to:
determine whether sensor signals have been received from the vehicle, the sensor signals selected from a set of sensor signals that include environmental conditions, vehicle conditions, and presence and location of other vehicles and pedestrians proximate to the vehicle; and
adjust the valid image data based on the sensor signals to generate the image.
16. The CMOS backplane of claim 11 , wherein the controller is further configured to:
determine whether valid image data has been received at the image frame buffer by determining whether valid vehicle image data has been received for a set of multiple image frames to display a particular image for each of the set of multiple image frames; and
in response to determining that valid image data has been received at the image frame buffer for the multiple frames, repeat driving the LED array using the image data for another set of multiple image frames.
17. The CMOS backplane of claim 11 , wherein the controller is further configured to control the driver to set ramp times and pulse width to drive each LED pixel to generate the image.
18. The CMOS backplane of claim 11 , wherein the controller is further configured to control groups of pixels of the LED array as individual blocks, the image data being partially refreshed to alter the image by only the groups of pixels associated with the partially refreshed image data.
19. A vehicle headlamp system, comprising:
a light emitting diode (LED) array;
a driver configured to drive the light emitting diode (LED) array to generate an image from a vehicle based on image data supplied thereto;
an image frame buffer;
a standby image buffer coupled to the image frame buffer, the standby image buffer configured to hold sets of standby image data;
a command and control module coupled to the image frame buffer and the standby image buffer, the controller configured to select one set of the standby image data for transmission to the driver to generate an image by the LED array in response to a determination that the image frame buffer does not contain valid image data to supply to the driver; and
at least one filter configured to provide filtered power to components of the vehicle headlamp system.
20. The vehicle headlamp system of claim 19 , wherein the at least one filter is configured to provide at least power protection selected from a set of power protections that include electrostatic discharge (ESD) protection, load-dump protection, alternator field decay protection, and reverse polarity protection.