DTF Glossary
LPI (lines per inch)
LPI is a halftone frequency: the number of screen cells or nominal lines per inch. In a raster implementation, cell size is derived from image pixels per inch divided by LPI. Higher LPI creates smaller cells at the same raster density, but does not guarantee more usable detail through a given printer and material process.
In practice
For example, 300 PPI divided by 50 LPI gives a nominal six-pixel cell. Rounding, dot method, angle, resampling, and RIP screening can change the realised pattern.
Always tie LPI to known physical size and raster density, inspect the full-resolution output, and run a controlled print. A zoomed preview cannot establish dot survival or hand feel.