as he explained earlier , laser diode cannot be analog modulated , u can only on or off it (digital modulation), and then whole ckt to be digital so make it work at full speed .(DAC takes time )erique82 said:Yeah, you are right. But what do you mean by "going digital" from the beginning? are they any other easier means to achieve distance measurement by laser? Besides triangulation method, of course. That's rather too simple.