This paper presents an innovative interdigitated photoconductive antenna (PCA) for terahertz applications that integrates a cylindrical lens array (CLA) with plasmonic nano-grating structures. The CLA focuses incident pulse laser emissions onto the interlaced active area to reduce destructive interference of the terahertz emissions and increase the terahertz pulse emission amplitude by 2.7 times compared to a conventional shadow mask approach. Optical absorption is enhanced by the highly localized electric field near the integrated nano-grating. The two innovations combined increase the peak-to-peak amplitude of the terahertz emissions 5.5 times for the device compared to alternative designs.