Atonm Knowledge Base | Principles and Applications of Fiber Optic Sensors

Abstract: Fiber Optic Sensor is a detector used to sense whether a target has reached a position. It is mainly based on straight-line light propagation: the detected object blocks or reflects the light beam and the synchronous circuit connects the circuit. Fiber optic sensors are primarily used to confirm whether an object has arrived at a detection position and thus provide object positioning. Due to their low cost, fiber optic sensors are widely used.

Principle of Fiber Optic Sensors

Fiber Optic Sensor is based on straight-line light propagation. The sensor detects object presence by blocking or reflecting the light beam, causing the synchronous circuit to change state. Common types include:

1. Through-beam fiber

2. Retro-reflective fiber

3. Diffuse-reflective fiber

Below we examine these three types of fiber optic sensors in more detail:

1. Through-beam Fiber Optic Sensor

The emitter emits signal light and the receiver receives it. If an object blocks the beam, the receiver no longer detects the signal. Output becomes 1 when an object is present, 0 when absent.

2. Reflective Fiber Optic Sensor

The emitter and receiver are combined. The emitter sends signal light which is reflected back when it meets an object; the receiver detects the reflected light. Output 1 indicates presence, 0 indicates absence.

3. Retro-reflective Fiber Optic Sensor

The retro-reflective type is similar to the reflective sensor and is mainly used for translucent objects. A reflector behind the object returns the beam through the object to produce a similar reflection effect to opaque objects.

Applications of Fiber Optic Sensors

Fiber Optic Sensors are mainly used to confirm whether an object has reached a detection position and thus for object positioning. Due to their low cost, they are widely used.

* Line product positioning

Use fiber optic sensors to detect whether a workpiece has reached the target position for the next processing step;

* Product counting

Use fiber optic sensors to count items passing a point over time.

* Equipment position detection

Use fiber optic sensors to monitor equipment movement and output a signal when reaching a target point.

Atonm currently offers two fiber sensor models:

1. Fiber Optic Sensor FA1-S

   

·  1. Switch or analog output selectable;

·  2. NPN or PNP selectable;

·  3. Single-signal or dual-signal selectable;

·  4. Normally open/closed interchangeable, with delay function;

·  5. Fastest response up to 50μs;

·  6. Powerful functions: counting, zero shift, auto gain, anti-light interference, rising/falling edge modes, percentage mode, etc.

2.Fiber Optic Sensor FA1-E

·  1. Zero shift, saturation recovery and anti-light interference functions;

·  2. Powerful features with response speed up to 50μs;

·  3. Normally open/closed interchangeable with delay function;

·  4. NPN or PNP output;

·  5. Easy operation with one-button control and delay detection function;

·  6. Switch or analog output.