PSD

How good is the position resolution?

This depends on each product. See the datasheets. Position resolution varies with the light level, interelectrode resistance, and resistance length.

What effects are caused by a large interelectrode resistance?

The position resolution improves. However, the saturation current becomes low, so saturation is prone to occur. The response speed also degrades.

How does the interelectrode resistance relate to the position resolution?

The position resolution is defined by "(Noise current/Signal photocurrent) × Resistance length." The larger the interelectrode resistance, the smaller the noise current. Therefore, the larger the interelectrode resistance, the better the position resolution.

How does the incident light level relate to the position resolution?

The position resolution is defined by "(Noise current/Signal photocurrent) × Resistance length." The signal photocurrent is proportional to the incident light level, so the larger the incident light level, the better the position resolution. However, excessive incident light level will cause saturation, so the incident light level must be set within a range where the PSD will not become saturated.