<prompt> True regarding the use of head mirror isare?Applied on right eyeFocal point should be within 6 inchesOne eye should be closed while examiningBoth eye should be open while focusing  <response>: Answer- A. Applied on right eyeTwo types of illumination is used in otolaryngologcial examination:Semi mobile illumination like the Bulls lampMobile illumination like the Clairs head light, or cold light based head bands.Bulls lamp: is a semi mobile source of illumination.The approximate focal length of the mirror is about l0 inches.The mirror is fured over the right eye in such a way pa of the mirror touches the nose.The minor is adiusted while keeping the left eye closed and the right eye is kept open to focus. Then both eyes are opened while examining. 