Laser break beam sensors are usually kind of cumbersome. They work by detecting an object breaking a laser beam - but you usually have to set up a laser on one end and a sensor on the other. Unless your sensor is big, it can easily get out of alignment.
...but not this break beam sensor. It has a light sensor+lens next to the laser to detect the reflected dot when the beam is broken, so it can sense when someone breaks the beam from the starting location. There's no need for a matching end point sensor! It forms a good strong laser with a sensing distance of up to 1 meter. Adafruit found that it can go a little further depending on the ambient light and the color of the thing distrupting it. You'll want something that is good at having the dot show up soft textures may not work as well. Adafruit used a hand, paper, or cardboard box with great success!
Set up is pretty easy, connect 5VDC to the red wire (you really do need 5V, 3V wont work!), Ground to the black wire and a pullup resistor on the output pin. You can have the pullup go to any voltage really. When the beam is broken, the output blue wire will pull down to ground. If it's being pulled up, the voltage will be 'high' when there's nothing in the way of the beam. There's a potentiometer which can be used to adjust sensitivity, Adafruit didn't find it to make much difference.
Emitter: 1mW red laser diode
Sensing Distance: Up to 1m (depending on light levels, contrasting material)
Operating Voltage: DC 4.5 VDC - 5.5VDC
Operating Current: 25mA
Output Current (NPN transistor output): 100mA max
Sensing Angle: <10 degrees
Response Time: 2ms
Working Environment: Indoor (not waterproof!), 0-70 degrees C
Dimensions w/components: 20mm x 18mm x 10mm / 0.8" x 0.7" x 0.4"
Cable Length: 250mm / 9.8"
This product is listed in:
Documentation and Resources:
- The Maker Revolution
The Maker Revolution celebrates the creation of new devices and the modification of existing ones - the transition from a consumer buying goods to eventually having a major part in their creation. The Maker Revolution places strong emphasis on free (...
We deliver Australia-wide with these options:
- $3 for Small Items (4-6 days, not tracked, only available on selected small items)
- $6.95 for Standard Post (2-4 days, tracked)
- $8.95 for Express Post (1-2 days, tracked)
- Pickup - Free! Only available to customers who live in the Newcastle region (only after we email you to notify your order is ready)
International Orders - the following rates are for New Zealand and will vary for other countries:
- $11.49 for Pack and Track (3+ days, tracked)
- $16.50 for Express International (2-5 days, tracked)
If you order lots of gear, the postage amount might increment based on the weight of your order.
Our physical address:
Unit 18, 132 Garden Grove Parade
Please checkout our customer service page if you have other frequently asked questions such as "do we do purchase orders" (yes!) or "are prices GST inclusive" (yes they are!). We're here to help - get in touch with us to talk shop.