Abstract: A small size and lightweight light beam scanning device for scanning a laser beam to perform an operation under an operating microscope. A movable mirror is provided which occupies only a small central portion of the objective lens of the microscope. Horizontal rotary shafts are provided on an annular pivot frame outside the field of vision of the objective lens. Rotational movement around the horizontal axis is transmitted vertically downwardly from the center of the movable mirror by a lever mechanism. A vertical bearing mechanism permits the movable mirror to turn around the vertical axis together with the lever mechanism. Rotational movement around the vertical and horizontal axes is transmitted through a universal joint to a gimbal system operating lever by a single lever.

Abstract: A counterbalance mechanism for a laser knife device which includes a manipulator in which the overall height of the balance mechanism is quite short and all rotational moments of the manipulator are cancelled for all operative positions thereof. A base support arm is rotatably mounted around a short first hollow arm with a second hollow arm extending through upright portions of the base support arm joined at its two ends through articulations to the upper end of the first hollow arm and a third hollow arm. A parallelogram link mechanism is formed including the upright members of the base support arm, first and second substantially parallel support arms and a third substantially vertical support arm upon which a counterbalance weight is mounted. One end of the first support arm is pivotably mounted between the upright members of the base support arm while the corresponding end of the second support arm is pivotably mounted around the second hollow arm between the upright members.