Lazer Security Alarm

this is a lazer security device that'll alarm u when something comes in the contact of the lazer beam and will be very helpfull

shouldering iron
shoulder wire
LDR
resistors 100ohms×2
transistors bc548 ×2
led
lazer diode
wires
pcb
buzzer(optional)
3v battery pack

The above given circit is of the reciver the lazer beam will touch the ldr and if something will block the path of lazer beam the ldr will complete the circit thus activate the buzzer and led

this is a rough demo of the wiring to be done on pcb

in the final assembly choose a dark place to do it and pogition the laser to the ldr. u may add a relay to the circit and connect it to an appliance lice ur room light as u enter the room lights and fans would. turn on on thier own