As organic dyes with excellent thermal and light stability, phthalocya
nine compounds have been investigated as write-once read-many optical
recording materials. By selecting different substituents and metallic
ions, the absorption bands of thin film of phthalocyanine compounds we
re matched with the wavelengths of semiconductor lasers. It was found
that the absorption regions of vacuum sublimated thin films of vanadyl
phthalocyanine (VOPc), tetra-pentyloxy phthalocyanine vanadyl (TPPcVO
) and tetra-nonyloxy phthalocyanine vanadyl (TNPcVO) were between 580
and 850 nm. In the near-IR region, the absorbance and reflectivity of
thin films of VOPc were greater than 50%, and 20% respectively. The st
atic optical recording test of the VOPc thin film showed that the writ
e power was less than 10 mW with the write pulse width of 200 ns using
an I-Ie-Ne laser as light source. The dynamic optical recording test
of VOPc as a write-once read-many recording material on a 5.25 in opti
cal disk indicated that the carrier-to-noise ratio (CNR) was greater t
han 45 dB.