Designing Special Messages with Burning Patterns in a Microwave Oven
Shreya Deshmukh, Masaki Aijima, Hirokazu Kawana, Yuta Sugiura, Naoya Koizumi, and Masahiko Inami


We propose a method of embedding hidden messages in gifts that burn into visible patterns when microwaved (called Phoenix-letters). Patterns or messages are hand-drawn by the sender on paper (for example, a greeting card) with graphite and covered in black paint to make them invisible. The recipient places the card inside a microwave oven so that the graphite will burn the paper along the drawing lines, causing the hidden messages or drawings to appear. The exciting element of surprise, and caring shown by hand-drawing, would appeal to the recipient of the gift and add to his/her happiness. This method can be applied to embed messages in food, for example by painting a pattern on dried seaweed (nori) with shūji ink, which also burns through hen microwaved. Phoenix-letters makes simple use of existing technologies to provide an interesting way to give gifts and send messages, and a way to embellish them so they are more sensational for the recipient.