註釋 "A study was made of the desirability of floodlighting in conjunction with transillumination of cockpit-type dial instruments and of control panels. In one phase of the present study a series of tests was conducted utilizing a special dial reader. Error scores were obtained of four selected subjects reading red transilluminated dial markings in a series of several brightnesses, with no floodlighting and with several levels of floodlighting. Opinions of subjects on the desirability of the various illuminating conditions were noted. Reading performance in these test situations did not improve significantly above 0.04 foot lamberts of transillumination on the markings. The addition of floodlighting with transillumination at this level resulted in a subjectively more comfortable reading situation even though errors in reading did not show significant differences. In a second phase of this study, fifteen experienced pilots, while seated in a cockpit mock-up selected the combination of red transillumination and red floodlighting which they would prefer for night flying. From the data obtained, it is concluded that a fixed level of supplementary floodlighting should be used with any selected level of indirect lighting in the cockpit lighting installation. This floodlighting level would serve to provide the pilot with better cockpit orientation and visual comfort. In addition, two other floodlighting levels are proposed to satisfy the pilot lighting needs when transillumination has failed and when the pilot is not dark adapted. These three levels are recommended for the "dim", "medium", and "bright" positions of the three-position selector switch."--Abstract 