The metastable O(D-1) atom produced in the photodissociation of O-2 in the wavelength region 113-130 nm was detected by measuring the 762 nm fluorescence of the transition O-2(b (1)Sigma(g)(+)--> X (3)Sigma(g)(-)). The excited states of O-2 were classified as either the (3)Sigma(u)(-) state that produces O(D-1) + O(P-3), or the (3)Pi(u) state that produces O(P-3) + O(P-3). Our quantum yield measurements of O(D-1) found bands of both pure and overlapped (3)Sigma(u)(-) and (3)Pi(u) states. Five bands were found to produce O(D-1), including the longest, second, and third bands and two additional bands near 115.3 and 113.8 nm that were assigned as the E (3)Sigma(u)(-)(upsilon' = 3-4) states. Three bands were assigned to the F (3)Pi(u)(upsilon' = 0-2) state. We also found a state at 116.2 nm, which did not produce O(D-1), but produced weak visible fluorescence. The possibility of attributing the fluorescence to a transition D (3)Sigma(u)(+)-C (3)Pi(g) was discussed.