JPH0552061B

PURPOSE:To reduce the influence of air fluctuation by a heater, by inserting a heat blockout optical transparent substance in the optical space for dividing the optical space into two parts. CONSTITUTION:A pellet 1, a material to be bonded, is mounted on a lead frame 2 by die bonding and is carried to a position where it is bonded. With a heater 5 and a bonding equipment 13 equipped below a stage and an ITV camera 6 equipped above the material 1 to be bonded, the specified bonding operation is conducted on the information gained from the camera 6 about the position of the material 1 to be bonded. Then, a heat blockout optical transparent substance 20 is inserted in the optical space between an object lens 9 of the ITV camera 6 and the material 1 to be bonded. By inserting the optical transparent substance 20, the optical space is divided into two parts so that the distance B between the object lens 9 and the optical transparent substance 20 is longer than the distance A between the optical transparent substance 20 and the material 1 to be bonded. By this method, an image distortion by the influence of air fluctuation is reduced and a very accurate bonding is ensured.