1. Science and Data Acquisition LASER Security Systems – Level 2

2. Did Mr. Ochs check your work for part 1?
Before you continue…
Did Mr. Ochs check your work for part 1?

3. What You’ll Learn… Stuff You’ll Need…
How to make a door chime that is activated when someone breaks or crosses a LASER beam
How to setup a perimeter security system
How to setup a grid security system
Stuff You’ll Need…
LASER and its power adaptor
Security System and its power adaptor
Photometer/Receiver (speaker) and power adaptor
(3) front surface mirrors
(2) audio patch cables

4. What You Should Know…
It is very important that you know and follow all the LASER safety rules to prevent injury
How to handle the LASER equipment carefully to prevent accidental damage to the equipment
How to properly store the LASER communication equipment when you are finished for the day

5. Do It! Make a Door Chime
Sometimes small retail stores are operated by just one or two people. When customers enter their store they need a pleasant sounding alarm to alert them that someone needs their assistance. Your security system in your LASER Communications kit can be setup to accomplish this task.
Power Adaptor
Power Adaptor
Photometer/Receiver
(speaker)
LASER
Security System
Power Adaptor

6. Do It! Examine the Security System
The Security System is packaged in an acrylic box like the LASER, but it is not a laser. It is the target or receiver of the laser beam, and it generates an alarm sound when the laser beam quits hitting its target.
Reset
Button
Yellow
LED
Front View
Back View
AMP
(speaker)
Back View
Target

7. Door Chime Setup
Security
System
You may need to use a shim to adjust the height of your laser in order to align it with the Security System target
Paper Shim

8. Do It! Test Your Door Chime
When you get your door chime setup, your laser sends a modulated signal across the laser beam to the target of the security system box. That signal then loops back to the laser through the audio cable. If you break the laser beam your speaker should beep. When your laser beam is properly hitting the target a yellow LED should light up.
The red reset button must be IN for this door chime, otherwise the alarm will not stop
Press Reset Button IN
Power Adaptor
Speaker Receiver
LASER
Security System
Audio Cable

9. Do It! Perimeter Security System
Pretend that you want an alarm system to secure your backyard. Could you expand your door alarm system to accomplish this? Now you will need your mirrors.
Mirror #2
Mirror #1
Speaker Receiver
Mirror #3
Security System
LASER
Power Adaptor

10. Do It! Perimeter Security System
You will find three front surface mirrors in your Laser Communications kit. What is a front surface mirror? Well, your bathroom mirror at home is a back surface mirror. The clear glass is in front with a reflective surface painted on the back of the glass. If you use back surface mirrors with your laser (which you can do) the glass will reflect and refract some of the beam, thus reducing the strength and concentration of the continuing beam. With front surface mirrors the laser beam does not have to pass through the glass, the beam hits the reflective surface immediately.
The blue protective plastic needs to be removed if your kit has never been used.
Adjustment Screw

11. Do It! Laws of Reflection and Refraction
These diagrams will help you better understand why you need to use front surface mirrors to bounce your Laser around. You can also go online to learn more about the laws of physics and the terms involved. Try entering “ray optics” light refraction” and “light reflection” into your favorite search engine to find out more
Laser beam is now split
Angle of Incidence
Angle of Incidence
Angle of Reflection
Laser Beam
Ghost
Laser Beam
Angle of Reflection
Reflective Surface
Air
Air
Back Surface Mirror
Front Surface Mirror
Glass
Glass
Reflective Surface
Angle of Refraction

12. Do It! Perimeter Security System
This setup is much more challenging. Turn everything off except the laser. You will need to carefully set up each mirror, one at a time starting with mirror #1. Use the little adjustment screw on the base of the mirror to direct the beam where you want it to go. When you get the 3rd mirror to aim the beam at the security unit target, carefully turn the speaker and security unit on. It might take some effort and tweaking to get it right.
Mirror #2
Mirror #1
Speaker Receiver
Mirror #3
Security System
LASER
Power Adaptor

13. Press and Release Reset Button
Do It! Perimeter Security System
When all your mirrors are properly adjusted so that your alarm system beeps when you break the laser beam, carefully press and release the RESET button to arm the alarm. Once you have it armed try breaking the laser beam. What happens? It should now sound the alarm continuously until you press the RESET button again to turn it off.
Mirror #2
Mirror #1
Press and Release Reset Button
Reset Button Out
Speaker Receiver
Mirror #3
Security System
LASER
Power Adaptor

14. Do It! Grid Security System
Pretend that you want to protect your candy from those who would try to sneak a piece when you are not looking. How would you do it? What entry points would you need to block?
Would a perimeter security system adequately protect this pile of candy?

15. Do It! Grid Security System
Think creatively about this problem.
What are different ways you can use the mirrors to bend or move the laser around the room?
Candy
Mirror #1
Power Adaptor
LASER
Mirror #2
Mirror #3
Speaker Receiver
Security System
Power Adaptor