Invisible Woman render other people or objects fully or partially invisible too, affecting up to 40,000 cubic feet (1,133 cubic meters) of volume. She achieves these feats by mentally bending all wavelengths of visible, infrared, and ultraviolet light to bend around herself or her target without causing any visible distortion effects. According to the "Women of Marvel: Celebrating Seven Decades Handbook", Sue's retinas don't function conventionally and instead of just registering objects using reflected light, the retinas in Sue's eyes also interpolate shapes based on reflected cosmic rays, which in the Marvel Universe are always present in the atmosphere, granted usually only
Invisible ink writing with soap water may be made visible either by heat, reaction with phenolphthalein, viewing under ultraviolet light, or by placing the page inside an iodine fume cupboard. Some of these are organic substances that oxidize when heated, which usually turns them brown. For this type of "heat fixed" ink, any acidic fluid will work. The most secure way to use any of the following substances for invisible ink is by dilution, usually with water, close to the point when they become difficult to develop. The writing is rendered visible by heating the paper, either on a radiator, by ironing