C and 2D are a front-side perspective view, rear-side perspective view, front view, and side view, respectively, of the camera;FIG. 3A is a sectional view taken along line IIIA--IIIA of FIG. 2A;FIG. 3B is a sectional view taken along line IIIB--IIIB of FIG. 2A;FIG. 4 is a view showing a mounting mechanism of the camera and a camera mounting portion of the personal computer;FIG. 5 is a view showing