DLPS193A November 2020 – July 2022 DLP500YX
PRODUCTION DATA
During a given period of time, the landed duty cycle of a given pixel follows from the image content being displayed by that pixel.
For example, in the simplest case, when displaying pure-white on a given pixel for a given time period, that pixel operates under a 100/0 landed duty cycle during that time period. Likewise, when displaying pure-black, the pixel operates under a 0/100 landed duty cycle.
If the use case involves inputting Grayscale input images, between the two extremes (ignoring for the moment color), the Landed Duty Cycle tracks one-to-one with the gray scale value, as shown in Table 7-1.
GRAYSCALE VALUE | LANDED DUTY CYCLE | |||
---|---|---|---|---|
0% | 0/100 | |||
10% | 10/90 | |||
20% | 20/80 | |||
30% | 30/70 | |||
40% | 40/60 | |||
50% | 50/50 | |||
60% | 60/40 | |||
70% | 70/30 | |||
80% | 80/20 | |||
90% | 90/10 | |||
100% | 100/0 |
Accounting for color rendition (but still ignoring image processing) requires knowing both the color intensity (from 0% to 100%) for each constituent primary color (red, green, or blue) for the given pixel as well as the color cycle time for each primary color, where “color cycle time” is the total percentage of the frame time that a given primary must be displayed in order to achieve the desired white point.
Use the following equation to calculate the landed duty cycle of a given pixel during a specified time period
where
For example, assume that the red, green, and blue color cycle times are 50%, 20%, and 30% respectively (in order to achieve the desired white point), then the landed duty cycle for various combinations of red, green, and blue color intensities would be as shown in Table 7-2 and Table 7-3.
CYCLE PERCENTAGE | ||
---|---|---|
RED | GREEN | BLUE |
50% | 20% | 30% |
SCALE VALUE | LANDED DUTY CYCLE | |||
---|---|---|---|---|
RED | GREEN | BLUE | ||
0% | 0% | 0% | 0/100 | |
100% | 0% | 0% | 50/50 | |
0% | 100% | 0% | 20/80 | |
0% | 0% | 100% | 30/70 | |
12% | 0% | 0% | 6/94 | |
0% | 35% | 0% | 7/93 | |
0% | 0% | 60% | 18/82 | |
100% | 100% | 0% | 70/30 | |
0% | 100% | 100% | 50/50 | |
100% | 0% | 100% | 80/20 | |
12% | 35% | 0% | 13/87 | |
0% | 35% | 60% | 25/75 | |
12% | 0% | 60% | 24/76 | |
100% | 100% | 100% | 100/0 |