I noticed in one of the articles about the device used to treat cold sores with 1072nm NIR that they claim that water is opaque to most of the IR spectrum, EXCEPT for a "window at 1072nm". So, could an ordinary infrared heating lamp be used as the source? I found sources for industrial IR lamps too. However, one can buy 250W IR heating lamps of the type used in bathrooms or to keep food warm in restaurants for about $3. Could a ziplock bag full of water be used as a filter to block the heating IR while allowing the 1072nm light to pass? Since the treatment time per day is short, about 10 minutes, such a lamp connected to a timer switch and a bag full of distilled water might be a real cheap source for this light.