An electron beam apparatus comprises a TDI sensor 64 and a feed-through device 50. The feed-through device has a socket contact 54 for interconnecting a pin 52 attached to a flanged 51 for separating different environments and the other pin 53 making a pair with the pin 52, in which the pin 52, the other pin 53 and the socket contact 54 together construct a connecting block, and the socket contact 54 has an elastic member 61. Accordingly, even if a large number of connecting blocks are provided, the connecting force may be kept to such a low level as to prevent the breakage in the sensor. The pin 53 is connected with the TDI sensor 64, in which a pixel array has been adaptively configured based on the optical characteristic of an image projecting optical system. That sensor has a number of integration stages that can reduce the field of view of the image projecting optical system to as small as possible so that a maximal acceptable distortion within the field of view may be set larger. Further, the number of integration stage may be determined such that the data rate of the TDI sensor would not be reduced but the number of pins would not be increased as much as possible. Preferably, the number of line count may be almost equal to the number of integration stages.