Leica D-Lux Typ 109 has a
13.0MP Four Thirds (17.3 x 13 mm ) sized CMOS sensor . On the other hand, Panasonic G85 has a
16.0MP Four Thirds (17.3 x 13 mm ) sized CMOS sensor .
One other difference between these two cameras that is worth mentioning is that Panasonic G85's sensor doesn't have an anti-alias (Low-Pass) filter. Removing anti-alias filter increases the sharpness and level of detail but at the same time, it increases the chance of moiré occurring in certain scenes.
Below you can see the D-Lux Typ 109 and G85 sensor size comparison.
Leica D-Lux Typ 109 and Panasonic G85 have the same sensor sizes so they will provide same level of control over the depth of field when used with same focal length and aperture. On the other hand, since Leica D-Lux Typ 109 has 24% larger pixel area compared to Panasonic G85, it has potential to collect more light on pixel level hence have less noise in low light / High ISO images.