urgent: need help for project

can anyone help me with the computation of the time lag on transmitting an infrared signal? if you have datas then its much better.hehe..

IR light, strangely enough, travels at the speed of light!.

hi wowowee,

If you look at the data sheet for the IR emitter it will/should give the rise
time of the radiated IR energy level from the time you apply the excitation voltage.

Is this what you mean ?

Depending upon the type of emitter it can 1 to 100 nanosec or greater.
Check the spec sheet

As pointed out, once its emitting vel= 300,000,000m/sec is close enough.

Regards
EricG