TB200 Optical Power Meter (DISCONTINUED)

The TB200 Optical Power Meter has been optimally designed for application in the manufacture of next-generation optical disks, DVDs and CDs. The TB200 enables virtually error-free measurement even without measurement of the wavelength of the laser diode used on optical disks. 
 

• Flat sensitivity characteristics in the 405 nm (blue), 660 nm (red) and 785 nm (near infrared) wavelength bands
• Sufficient margin provided by 18 mm dia. sized photo-receiving surface even at high NA (0.85)
• Influence of multiple reflection alleviated by low-reflectivity sensor surface
• High-power measurement up to 100 mW supported
• Measurement interval of about 100 msec achieved
• Full remote control enabled by standard USB interface

What's more, a major feature of the TB200 is its large 18 mm diameter sensor. With this sensor, you no longer need to check accuracy of the sensor in lens optical systems whose high numerical aperture (NA) is 0.85.

Sensitivity Characteristics

Sensitivity characteristics easily applicable in wavelength bands used by optical disks

Conventional optical power meters, that use a silicon sensor, have sensitivity characteristics that are dependent on the wavelength in all measurement regions. For this reason, the light emission wavelength must be known beforehand to ensure accurate measurement. The TB200, however, has been designed so that its sensitivity characteristics are flat near the blue (405 nm), red (660 nm) and near infrared (785 nm) wavelength bands, which are used by various optical disks. As a result, the TB200 can measure with little error independently of light emission wavelength.
 

Stable Measurement

Stable measurement independent of distance from lens

As conventional optical power meters do not perform processing to prevent reflection on the sensor surface, multiple reflection occurs between the sensor surface of the optical power meter and the lens holder, for example, of the optical pickup that emits the laser. As a result, correct measurement is not possible at some distances from the lens. The TB200, however, performs anti-reflection processing to prevent the influence of multiple reflection.
 

Photo-receiving Sensor

Large 18 mm dia. photo-receiving sensor ideal for picking up high NA light

Surface sensitivity

Relative surface sensitivity distribution ±2 mm area from center: approx. 99.5% ±5 mm area from center: approx. 99%

With high NA (numerical aperture) lenses, the sensor must be brought close to the laser emitter to ensure accurate measurement as these lenses have a large angle of incidence. As the maximum angle of incidence of lenses having 0.85 NA is about 60 degrees, the light receiving area is 10 mm in diameter at a distance of 3 mm from the focal point. The light receiving diameter of the TB200’s sensor head is 18 mm (effective diameter: 14 mm or more). This means that stable measurement can be obtained using light emitted from high NA lenses even if the sensor is not accurately positioned.

Sensor Head Designed for Use in Production Lines

 When the Optical Power Meter is used in production lines, the sensor is sometimes attached to manufacturing equipment or jigs. The TB200 has been designed so that the thin optical sensor module can be easily detached from the sensor head.

Note: Product quality is assured when the pptical power meter is shipped from the factory with its sensor mounted in its case.

If the user removes the sensor from its case for use, the quality warranty will be voided.

Full Remote Control Enabled on the USB Interface

The capability for fast and full remote control is required on automated production lines. All TB200 functions can be fully remote-controlled at high speed on its USB interface. Measurement results can also be sent to a PC over the USB interface.

Block Diagram

	With protector attached