 one second i'm focusing okay i am now focused very recording hello who are you great and what is this interesting and what does it do it measures the spectrograph it takes a spectrograph of different kinds of liquids here the samples the light that will shine through a slit and then there will be a grating inside in this case a cd disk that will record its findings to the computer great and we want to test the sample take one for instance this is uh oil the polluted mineral oil we can so so when you put it here i'm looking at the screen at the same time yeah so that's that's the spectrometer of all the these are almost all the colors that absorb everything about the right you mean yes i see and you're saying it's also a fluorospectrometer so what do you mean by fluorospectrometer well actually and what is this button as well oh this adjusts the brightness and intensity of the bulb so you can adjust the you and you can change the bulb if you understand you have different bulbs so this is a okay so you can actually change the bulb and change it often and change the intensity that's wonderful and we're going to see if the bulb fluoresces so we're going to use a 405 nanometer purple laser to identify yeah so we're going to use olive oil for test and then we turn it on we get nothing on the screen because it doesn't really fluoresce so there's nothing that fluoresces no in olive oil no it doesn't but so so this is normal yes okay that's that's great okay so now you've explained what is a spectrometer and a fluorospectrometer and you build this device yourself with the with the class with your comrades what's next uh we're going to ship this in percent called public labs they will have a lot of different spectrums there different kinds of oils different kind of liquids acids gases different kinds of balls etc that's great thank you so much and the last image i put the spectrum back so i put it back that's the spectrum from the hong kong harbour school