Canon SX620 HS has a 20.0MP 1/2.3" (6.17 x 4.55 mm) ) sized BSI-CMOS sensor and features DIGIC 4+ processor. On the other hand, Samsung TL500 has a 10.0MP 1/1.7-inch (7.44 x 5.58 mm ) sized CCD sensor .
Canon SX620 HS's sensor provides 10MP more than Samsung TL500's sensor, which gives a significant advantage in real life. You can print your images larger or crop more freely.
On the other hand, please keep in mind that Max sensor resolution is not the only determinant of resolving power. Factors such as the optical elements, low pass filter, pixel size and sensor technology also affects the final resolution of the captured image.
Below you can see the SX620 HS and TL500 sensor size comparison.
Sensor Size and Resolution Comparison image of Canon SX620 HS and Samsung TL500 Cameras
As seen above, Samsung TL500 has a 1.5x Larger sensor area than Canon SX620 HS. 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.