基于PWM的LED显示屏像素亮度控制方法  

Based on the PWM of the LED Display Pixel A Brightness Control Method

作　　者：邓宏贵[1] 梅卫平[1] 曹文晖[1] 敖邦乾[1] 

机构地区：[1]中南大学物理科学与技术学院,长沙410083

出　　处：《光电子技术》2010年第2期131-134,共4页Optoelectronic Technology

摘　　要：提出了通过综合控制发光二极管(LED)驱动芯片输出信号和全局使能信号的脉冲宽度调制(PWM)波形来控制显示屏像素亮度的方法。在基于二进制位权重PWM的基础上,分别研究了直接输出和全局使能控制LED屏像素亮度时,灰度级数与刷新频率和发光效率的关系。研究结果表明,随着灰度级数的增加,采用全局使能PWM方法控制的LED显示屏刷新频率要远远高于直接输出PWM,但全局使能PWM会带来发光效率降低的问题。采用直接输出和全局使能综合PWM的方法,并根据实际情况合理选择二者比例,可很好的兼顾显示屏刷新频率、灰度等级和发光效率,最大限度提高显示质量,增强显示效果。A method of controlling display pixel brightness is proposed through comprehen- sive control on LED driver IC output signal and global enable signal PWM waveform to control display pixel brightness. On the basis of the weight based on the PWM, relation among gray se- ries and refresh frequency and luminous efficiency is studied while the direct output and global enable control pixel brightness LED screen. The results show that as gray-scale series increase refresh of LED display through global enable PWM methods is higher than direct output PWM, but global enable PWM will bring about the problem of light-emitting efficiency reducing. By using the methods that synthesize the direct output and global enable PWM, choosing the ratio rationally between the two which based on the actual situation, a good balance of the refresh and gray level and luminous efficiency is realized, display quality is improved and display effects is maxi- mally enhanced.

关 键 词：全局使能 脉冲宽度调制 发光二极管 显示屏 亮度控制 

分 类 号：TN104.3[电子电信—物理电子学]