Astro optics pvt. Ltd. An iso 9001 : 2000 certified company manufactures various types of optical components and lenses are one of them. Astro optics pvt. Ltd. Presents a range of filters which are used to `filter` out light, which means to separate out wavelengths. Being a part of that heat filters are the short pass filters which transmit the visible light and absorb the ir radiation, thus not allowing the "heat" to pass through. Schott filters are used like kg1, kg3, kg5 etc. Heat filters can also be "toughened" if required.
