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Current time:0:00Total duration:2:53

What is inside a DVD player? (5 of 5)

Video transcript

okay so the way a DVD player works is there's a spinning disc right here that's our DVD and so it spins around and there is a underneath of it there is a motor and that motor spins causing the disc to spin and then there is a there's a lens and a reflector and a laser diode and the laser diode shines the light on the reflector it goes through the lens focuses on this the DVD and this whole part right here moves out as the DVD spins and what happens is the DVD reflects the light back down back down here and there is a light collector so the light collector says oh okay this is a pit or a bump and it sends that information via pulses of electricity back to the microprocessor so now we're going to look at the laser assembly it's comprised of a number of parts it has a laser diode has a series of reflectors it has a lens it has a laser or light sensor and it has an adjustment mechanism so the first thing I'm gonna do is take this covering off I had already loosened it to make it a little easier to get off you can see right here there are two neodymium magnets I think they're neodymium because they're very very strong for their size and that means it's a rare-earth magnet and they tend to be very very powerful permanent magnets and then right here you can see there are two different coils out of copper and there are two coils out of copper there and the lens is mounted on these wires in between and it can shift and move so I suspect that that mechanism allows for fine-tuning adjustments of the lens all right so let's go ahead and see if we can take apart this DVD player so we'll pop this prism off here so this sensor collects the reflected light and sends that information back and let's see if we can there we go and there's the laser diode so that's the little guy that shines the light that the laser light that gets red that hits the disc and gets reflected and red by this sensor