View Full Version : long range ir based obstacle detection doubt

11-23-2008, 01:51 AM
hello i am lavish
i want to detect a white obstacle at range of 60 cm.
can i use tsop 1738 for this range? if not what can be alternate solution to the problem?

11-24-2008, 12:51 AM
can be done using TSOP , but the emitted beam will have to be quite
directed. Actually depends on the application ? whats it about ?

11-25-2008, 12:24 AM
thanks for reply bro.

actually it is about a door 30*30*30cm. it is white in color.
we have to detect that is it open or close. it will be at 45cm distance.

i studied timer 555 and can generate 38khz frequency. but as tsop1738 data sheet says we have to provide pulses in burusts like deay after some pulses. how can we generate it using 555.

moreover how can we make it properly directed?

11-25-2008, 10:54 PM
modulate the 38 Khz with another frequency.

moreover how can we make it properly directed?

the beam of a pen torch :!: