laser alarm system - Electronic Circuits Projects Diagrams Free

ira thakur · 26th June 2006, 05:43 AM

i want to make a perfect laser alarm sys so if every body know pls help me i m in btech 2 year in ece

mramos1 · 27th June 2006, 12:44 AM

Does perfect laser mean the laser will kill the intruder? Or is it to be used to detect them?

More details if you want others to help you.

Papabravo · 27th June 2006, 03:47 AM

Yes, give us some way to distinguish a perfect laser alarm system from one which is less than perfect so we will know if we have succeeded or not. It's pretty hard to tell what done means with no measuring stick.

john1 · 27th June 2006, 03:57 AM

Hi,

Yes, i have tried to use those tiny cheap laser units as alarm beam
sensors, but over distances i find they 'spread' quite badly.
They are indeed far from perfect.
I was wondering about lens correction to try and reduce the spread.
But such a lens would hardly be a lens at all.

Then again, i may have misunderstood your rather sketchy post.

John

Papabravo · 27th June 2006, 04:10 AM

Beams of every type spread out over distance. It's what they do. A lens can focus a beam to a spot, but after that it diverges again.

Maybe that's OK, we still don't have any requirements from the original poster yet. If you shine a beam on a sensor and detect an interruption that would form the basis of an intrusion alarm. The problem is that you can see and avoid visible light. Every cheesy Holywood movie about art thieves will show you that. So what kind of radiation can be generated and detected which is not detectable with the eyes?

drewdrewdrew · 8th January 2008, 04:31 PM

infrared - drew

Papabravo · 9th January 2008, 12:23 AM

You sure about that? Last time I checked eyes are very sensitive to temperature. Can I shine an IR laser on your retina?

blueroomelectronics · 9th January 2008, 01:58 AM

More importantly where can I get sharks with lasers.

audioguru · 9th January 2008, 02:11 AM

People who have a laser intruder detector outside report that the beam misses the sensor and causes a false alarm when the wind makes them move a very small amount.

There is a tall free-standing transmitting tower in my city. It has a laser at its top that shines straight down. It moves very far when it is not very windy.

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26th June 2006, 05:43 AM	(permalink)
ira thakur	laser alarm system i want to make a perfect laser alarm sys so if every body know pls help me i m in btech 2 year in ece

27th June 2006, 12:44 AM	(permalink)
mramos1	Does perfect laser mean the laser will kill the intruder? Or is it to be used to detect them? More details if you want others to help you.

27th June 2006, 03:47 AM	(permalink)
Papabravo	Yes, give us some way to distinguish a perfect laser alarm system from one which is less than perfect so we will know if we have succeeded or not. It's pretty hard to tell what done means with no measuring stick.

27th June 2006, 03:57 AM	(permalink)
john1	Hi, Yes, i have tried to use those tiny cheap laser units as alarm beam sensors, but over distances i find they 'spread' quite badly. They are indeed far from perfect. I was wondering about lens correction to try and reduce the spread. But such a lens would hardly be a lens at all. Then again, i may have misunderstood your rather sketchy post. John __________________ ************************************************ ***************

27th June 2006, 04:10 AM	(permalink)
Papabravo	Beams of every type spread out over distance. It's what they do. A lens can focus a beam to a spot, but after that it diverges again. Maybe that's OK, we still don't have any requirements from the original poster yet. If you shine a beam on a sensor and detect an interruption that would form the basis of an intrusion alarm. The problem is that you can see and avoid visible light. Every cheesy Holywood movie about art thieves will show you that. So what kind of radiation can be generated and detected which is not detectable with the eyes?

8th January 2008, 04:31 PM	(permalink)
drewdrewdrew	infrared - drew

9th January 2008, 12:23 AM	(permalink)
Papabravo	You sure about that? Last time I checked eyes are very sensitive to temperature. Can I shine an IR laser on your retina? __________________ We never have time to do it right; but we always have time to do it over.

9th January 2008, 01:58 AM	(permalink)
blueroomelectronics	More importantly where can I get sharks with lasers. __________________ Bill Smart Kits build Smart People http://www.blueroomelectronics.com

9th January 2008, 02:11 AM	(permalink)
audioguru	People who have a laser intruder detector outside report that the beam misses the sensor and causes a false alarm when the wind makes them move a very small amount. There is a tall free-standing transmitting tower in my city. It has a laser at its top that shines straight down. It moves very far when it is not very windy. __________________ Uncle $crooge