Great interest has been shown in the physics and applications of Fabry-Perot optical microcavity. The spontaneous emission properties of a light emitting material

such as spectrum shape and emission distribution

can be tailored in optical microcavities that have dimensions comparable to an optical wavelength. Up to now

many applications with one-dimensional microcavity structures have been reported

such as resonant light-emitting diodes

vertical-cavity surface emitting lasers and microcavity organic light-emitting diodes (OLEDs). Microcavity OLEDs have shown abilities to reduce the emission bandwidth

improve the color purity

and increase luminous efficiency as compared to those of normal OLEDs. Coupled optical microcavity (CMC) is a structure consists of two or more planar Fabry-Perot microcavities that are coupled to each other. Lately

CMCs have been investigated to show very different emission characte-ristics compared with a single Fabry-Perot microcavity

which presents many potential applications

for instance highly selective wavelength filters

bistable devices

a range of optical and electro-optic switches. In this paper

spontaneous emission properties of a coupled optical microcavity based on an organic light emitting material have been studied under optical excitation for the first time. The structure of the CMC is glass/DBR

A

/filler/DBR

B

/tris(8-quinolinolato) aluminium (Alq

3

)/DBR

C

. The bottom cavity and top cavity were formed by DBR

A

/filler/DBR

B

and DBR

B

/Alq

3

/DBR

C

respectively. Compared with a broadband spectrum of Alq

3

film centered at 511nm

spectral narrowing and intensity enhancement at the two cavity modes 518

553nm was observed in CMC. The results indicate that CMC structure can strongly modifies the spontaneous emission properties of organic material. The CMC structure may be used as an efficient approach of improving luminous efficiency and can be used to develop potential new type organic photoelectric devices.