The obvious drawback of edge-lit Character LCD Modules

1, since the matrix the backlight in claim block must have precise control backlighting, generally speaking, the design of the circuit corresponding complex; addition, select, as well as some of the control chip of the LED chip can also cause an increase in cost.SPI 12864 lcds
In the assembly, the matrix backlight accordingly, the complexity of the process is much higher than the direct type and side-in. Therefore, the assembly yield, cost is also constrained its a major factor.
Matrix backlight compared to traditional direct type backlight, local dimming accuracy in the current view will be higher than the direct type, due to the direct type the next diffuser plate has been dodging occur, and the matrix is ​​the next diffusion film piece dodging influence between adjacent partition needs to be less than the direct type, finer control of the contrast. However, due to its partition was less affected each other, when in the event of a regional block damage to the LED, the optical effect of defects than the direct type looks significantly a lot. In addition, the thickness thereof is extremely obvious advantages. However, due to a partition of the matrix are relatively independent of one side into the backlight, the complexity of its institutions is much higher. At present, a lot of direct type on the the partition local control light through an area some LED light control, the matrix must be controlled for each sub-block, so that the circuit is correspondingly more complex.
Matrix side into to solve the local control light and Energy Smart greatly enhance picture contrast, relatively simple than thermal design; side into the light guide backlight distance below, the optical efficiency will be higher than the side-in, fully able to do in thickness comparable with the side into the backlight. The only side into the backlight or insufficient compared to the above-mentioned cost and manufacturing complexity. The the normal one light guide plate need to achieve through hundreds of partitions, means that its number of parts and assembly complexity correspondingly improved hundreds of times, due backlight Component is related to an assembly process, the defect rate I believe that is also a big problem.QVGA lcd