Panasonic ZS1 has a 10.0MP 1/2.5-inch (5.744 x 4.308 mm ) sized CCD sensor . On the other hand, Casio EX-H10 has a 12.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CCD sensor .
Below you can see the ZS1 and EX-H10 sensor size comparison.
Sensor Size and Resolution Comparison image of Panasonic ZS1 and Casio EX-H10 Cameras
As seen above, Casio EX-H10 has a 1.1x Larger sensor area than Panasonic ZS1. Larger sensors give photographer more control on the depth of field and blurry background compared to smaller sensor when shot in same focal length and aperture.