The photo-reflection-type multi sensor is composed of four LEDs (red, blue, green and infrared) and two light-sensitive sensors. It detects the leading edge, skewing,

and width of media and is used for adjustment of the registration, head height, and calibration.

During head adjustment, the light reflected by the infrared LED is detected by two light-sensitive sensors to calculate the head height from the difference between

the measurements.

Linear encoder

When the carriage modes, the linear encoder located at the rear of the carriage reads the slits on the linear encoder to detect the carriage position.

Lift cam sensor

This is a photo-interrupter-type sensor. The lift motor is driven by a predetermined number of pulses received after blocking of the sensor light by the flag, thus

controlling the heights of the head and platen.

Environmental temperature sensor

The environmental temperature sensor installed on the carriage PCB detects the temperature around the carriage.

The resistance of the thermistor that changes with the temperature inside the printer is reported to the main controller via the carriage PCB.

The environmental temperature is used to calibrate the head sensor and to detect abnormal head temperatures.

Head temperature sensor

The diode-type head temperature sensors installed at the top and bottom of the printhead nozzle unit are used to detect the head temperature.

The diode voltage that changes with the nozzle unit temperature is reported to the main controller via the carriage PCB.

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Linear encoder

Multi sensor

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