We fabricated the ceramic PLT tablet which was composed of 5, 10 and 15 mold lanthanum concentration and thin film PLT to develope pyroelectric materials, and investigated their characteristics. Using TG/DTA, we determined calcination and sintering temperature to sinter the PLT completely and to prevent volatilization of the Pb components. The calcination and sintering temperature were 850℃, 1150℃ respectively, end there was a lot of mass loss at higer sintering temperature. By measuring temperature-dielectric constant characteristics of ceramic tablet we investigated dielectric constant characteristics depends on La concentration. The Curie point of PLT with 5, 10 and 15 mol% lanthanum concentration were 330℃, 269℃ and 210℃ respectively. Using PLT cerarnie tablet we observed IR detection characteristics, and then deposited PLT thin film by rf magnetron sputtering. We verified that PLT thin film fabricated with completely sintered PLT target had the same structure to target by investigating lattice constant and optical transparency.