Development of an indirect view system for vehicles requires an appropriate method of its evaluation to achieve the purpose. Conventionally, evaluation by view area has been most frequently used in carrying out such development, without any method for evaluation by visibility. Under the circumstances, research was carried out to establish methods of evaluation by quantifying the size and distortion of the indirect view image. Using the results of this research work, a series of model tests were repeated to arrive at a periscope mirror system. This system excels all other mirror systems in image size, uniformity in distortion, view range, continuity with direct field-of-view and ease of use by drivers, and offers the best means of providing indirect view in heavy vehicles.
Abstract