TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Component: The optoelectric transducer uses metal complex and/or oxide semiconductor microparticles. The oxide semiconductor microparticles contains titanium dioxide, zinc oxide, or tin oxide. The oxide semiconductor microparticles (in the form of thin film) support the methine group pigment in the presence of an inclusion compound.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preparation (disclosed): The methine group pigment is obtained by reacting a carbonyl compound and a compound having active methylene in the presence of a basic catalyst (e.g. sodium methylate, diethylamine).Preferred Pigment: The methine group pigment is of formula (2), preferably of formula (3).R2-R7=H, optionally substituted aromatic residue or aliphatic hydrocarbon residue, or halogen.R2-R7 may combine with each other to form a ring having optional substituent. Benzene ring (b) has 1-5 substituents chosen from halogen, amide, hydroxyl, cyano, optionally substituted aromatic residue and aliphatic hydrocarbon residue, nitro, sulfonic acid group, carboxyl, phosphoric acid group, alkoxyl, acyl, and optionally substituted amino. Preferred Definitions:    n=0-6, preferably 0-4;    R1=optionally substituted 5-36C aliphatic hydrocarbon residue or aromatic hydrocarbon residue having 1-36C aliphatic hydrocarbon residue as substituent, phenyl group which has a 1-36C hydrocarbon residue as substituent, 9-14C aromatic-hydrocarbon residue (nitrogen atom may also be included in ring, and it is sufficient to substitute by 1-8C alkyl as substituent) which consists of 2-3 5- or 6-membered ring containing aromatic ring, preferably benzene ring, preferably 6-18C alkyl;    X=-CH2CH2-, -(CH2)3-, cyclopentane-1,2-diyl, or benzene-1,2-diyl;    Y'=carboxyl;    Z=phenyl; and    A1-A3=H.    SPECIFIC COMPOUNDS - 299 specific methine group pigments are disclosed. E.g. compound of formula (A).    EXAMPLE - A methine group pigment of formula (A) was obtained by dissolving a compound (1 pt. wt.) of formula (B) having active methylene and a carbonyl compound (1.5 pts. wt.) of formula (C) in ethanol (20 pts. wt.), adding piperidine (0.01 pts. wt.), heat-refluxing for 2 hours, and re-crystallizing the crystal obtained by cooling after reaction. The compound had a maximum absorption wavelength of 501 nm. The solar cell obtained using the methine group pigment had a short circuit current of 15.5 mA/cm2, a releasing voltage of 0.63 V, and a conversion efficiency of 6.8%.