Question
What is resolution?
Answer
The resolution is the width of the linear output variation when both the sensing object and Sensor are stationary. Even if both the sensing object and Sensor are stationary, the linear output value is not stable. It varies, and the width of this variation is the resolution.
The resolution is the ability to distinguish differences. It is used as the basis for judgments, but only a 10th of the required resolution is normally used. For example, if a resolution of 20 μm is required for a judgment, a Sensor with resolution capability of 2 μm should be used.
Caution:
The resolution does not represent the accuracy of the distance. It indicates reproducibility when positioning a sensing object. The resolution is defined for OMRON's standard sensing object (white ceramic), and depends on the type of sensing object.
The Smart Sensor has a resolution display function for easy confirmation of the resolution of the sensing object.
The resolution and response speed are mutually related. When the response speed is decreased, the resolution improves. Generally, when the averaging number is multiplied by a factor n, the resolution improves by the square root of n.
The response speed of the Smart Sensor and the averaging number can be set to any of 13 different levels, as shown below. The relationship between the averaging number and the response time is shown in the following table.
Averaging number | Response time (ms) |
1 | 0.3 |
2 | 0.5 |
4 | 0.8 |
8 | 1.5 |
16 | 2.5 |
32 | 5 |
64 | 10 |
128 | 20 |
256 | 40 |
512 | 75 |
1024 | 150 |
2048 | 300 |
4096 | 600 |
Relationship of Averaging Number and Response Time (with a Fixed Gain)