A heatshield assembly for a metal barrel of a firearm includes a heatshield body provided with a rear end extending to a front end, and configured to overlie the barrel of the firearm. A light source illuminates a sheet of paper and an optical collection system collects and filters the light diffusely reflected from the sheet of paper. A plurality of first holes is disposed extended through the first conductive layer, and has a mesh pattern to decrease the spread of vibration generated by the capacitor.