Sun Switch

Sun Switches are recurring items in the Legend of Zelda. These switches, whose shape is reminiscent of that of a stylized sun, unlock doors and make objects like Treasure Chests appear when they come in contact with light, either by means of light reflected from the Mirror Shield or from being hit by Light Arrows. When activated, their dormant "faces" light up with a disturbing smile. When hit by light, some Sun Switches burn away and summon Wallmasters from the ceilings.

The Legend of Zelda: Ocarina of Time
Sun Switches are found in certain areas, the most notable of these being in the Spirit Temple and Inside Ganon's Castle. Inside the Spirit Temple, Link must often uncover a source of light to reflect upon them, most often by blowing holes in cracks in the walls, allowing sun to shine through. Alternately, once Link has received the Light Arrow from Princess Zelda, they can be activated through means of these.

The Legend of Zelda: Majora's Mask
Sun Switches are commonly found in the Ikana region of Termina and the locations therein, such as the Ancient Castle and the Stone Tower Temple. Additionally, one Sun Switch serves as the means of unlocking the door to the Secret Shrine hidden in Ikana Valley. They can be activated much the same way as in Ocarina of Time. In addition to Sun Switches, Sun Blocks also appear, which impede Link's path.