ROHM has developed the “RPR-0730”, analog compact optical sensor, capable of high-precision detection of fast-moving objects. This sensor can be widely utilized in consumer and industrial equipment applications, including printers and conveyor systems.
As industrial and office equipment becomes increasingly sophisticated and automated, there is a growing demand for improved sensing technology accuracy. In applications such as label printers, material or product transport systems, and copiers, the need for technology that can identify objects more accurately is essential. Moreover, increased speed driven by productivity improvements makes the introduction of high-speed, high-precision optical sensors crucial.
The RPR-0730 is a compact reflective optical sensor (photo reflector). It employs an infrared VCSEL, which offers higher directionality than LEDs, enabling detection of finer objects. Furthermore, by using a phototransistor with analog output as the receiver, the sensor achieves a response time of 10µs. This dual combination enables high-speed, accurate identification of fine lines as narrow as 0.1mm － previously difficult to detect with conventional LED light sources. As an addition to the existing digital output sensor “RPR-0720” series, RPR-0730 expands capability to applications requiring faster sensing, such as print detection in copiers, label printers, or rotational detection in motors and gears.
The package is ultra-compact at 2.0mm × 1.0mm × 0.55mm and employs a visible light filtering resin to suppress interference from ambient light or sunlight. This enables stable detection even in environments with varying light conditions, such as factories or outdoors. The sensor can also be easily integrated into equipment requiring installation in small, confined spaces, like inside conveyors or precision instruments, making it suitable for a wider range of applications.
Mass production of the new product commenced in October 2025 (sample price: $2.2/unit, tax excluded). This product is available for online purchase from online distributors such as DigiKey and MOUSER.
Going forward, ROHM will continue to leverage its development expertise in light-emitting and light-receiving elements to create sensing products that meet customer needs, contributing to the miniaturization and enhanced convenience of various devices.
Application Examples
•Print detection, paper feed/jam detection in label printers, copiers, shredders, etc.
•Object detection of packages/specimens, workpiece position detection in conveyance systems, automatic inspection equipment, etc.
•Motor/gear rotational detection in industrial robots, etc.
Terminology
Photo reflector
A type of optical sensor combining an emitting element and a receiving element. It illuminates an object and detects the intensity of the reflected light to measure the presence or distance of an object.
VCSEL
Abbreviation for Vertical Cavity Surface Emitting LASER. A type of laser light source, it is a semiconductor laser that can emit light directly from its surface. Compared to LEDs, it offers higher directionality and is suitable for high-precision sensing. Originally adopted for optical communication applications, its use as a light source for proximity sensors and distance sensors has been expanding in recent years.
Phototransistor
A transistor-type photoelectric conversion element that converts optical signals into electrical signals. It integrates a photodiode and a transistor, controlling the base current with light to output an amplified collector current.
