In order to achieve the intended level of communication with visitors in museums where large displays are installed, it is essential to understand how various display factors affect visitors. We explore the effects of the display angle on individual users. In our experiment, we set up three types of flat displays - vertical, horizontal, and tilted - and comprehensively tested users' cognitive, behavioral, and subjective aspects. The results showed that a significant difference could be discerned in regards to cognitive and subjective aspects. Test results for the cognitive aspect showed that the display angle on which the displayed content was easy to understand and remember differed depending on age. Test results for the subjective aspect showed that irrespective of age, users rated tilted displays as being quicker to attract attention and easier to peruse, to understand and remember the content, and to interact with, and such displays were the most preferred.