Will it burn aka help with component choise

Hi Dear members

I'm going to build a small device to detect the direction of small objects on a convoy/slide/chute, and then seperate them into two lanes.... based on laser light.
It will be handling an object pr. sec. and can be run for 24h non-stop (most of the time 8h daily)

I've attached a drawing of the device I'm going to build, but it raises some questions to me...

a) I've made a small hole/channel on my device that is 4x4mm to narrow the laserbeam.
Will incapsulating the laser (as I've planned), make it extreemly hot or is that not a problem?
...should I drill holes into the laser housing/channel

b) I've got a 650nm laser (like this one... 5mw red line laser), and I'm currently looking to find a corresponding phototransistor... does anyone know one, or could anyone point to a better set of matching components for this purpose?

I will be using an Arduino Uno to controll the laser, phototransistor and servo.

Thank you a lot for your time and help!

Kind regards Taras

Any phototransistor sensitive to visible light will work, provided you know what you're doing with the rest of the circuitry.

As for your thermal question; the linked module consumes 20mA; if you run it from 5V that is 100mW of dissipation (minus ~5mW optical), which shouldn't be an issue for it.

Keep in mind that depending on how many I/O channels you are using and with what circuitry, you may not have the 20-25mA available from the Arduino. In such a case you will need a buffer/current amplifier stage (simple 2N2222A or a logic level n-ch FET would do).

Thank you!

I've just bought the BDY62 as ir receiver.

I think i'll circuit the power supply out seperately to each component/module, so it feeds the arduino (with a motor shield), the laser, the ir receiver, the stepper motor.
Trying to gather components so that all will be running 5V.

Then it should mearly be a question of having a good enough ps...

Wouldn't that do it?

Last but not least, the arduino will be feeding a central controller with a status (thinking perhaps daisy-chaining multiple arduinos).

regards T

sorry... not thinking... i'll be using a 12V PS for the stepper and motor driver

Taras said:

I've just bought the BDY62 as ir receiver.

Click to expand...

I think you missed the part where I said it needs to be sensitive to visible light. The silicon between the two styles will be similar, but IR receivers are often encased in a plastic that blocks visible light. (A red laser diode emits visible light). For example, here's one under regular light, followed by IR.





Besides, Google tells me the BDY62 is a standard NPN, not a phototransistor.

It's this one... Siemens - datasheet pdf
420nm-1130nm

I've just bought the BDY62 as ir receiver.

Click to expand...

It's this one... Siemens - datasheet pdf

Click to expand...

Sometimes 1 letter makes a difference after all eh?

I agree that you are unlikely to have thermal issues. The physical size of the module is such that there will be plenty of surface area to dissipate the heat unless you plan to encapsulate it in something with extremely low conductivity.