What Makes a Laser Power Meter So Expensive?
Commercial laser power meters cost $300 and up – $1,000 is a more typical price for something that works over a wide range of power levels and wavelengths. Where the precision and automatic wavelength calibration of these instruments is not needed, a basic laser power meter can be built inexpensively. See the section: Sam’s Super Cheap and Dirty Laser Power Meter and those that follow. There are several ways to design a device that will determine the power in a beam of light. Here are two: • Photodiode – each photon within the wavelength range of the device creates an electron-hole pair. When reverse biased, this results in a current flow which is proportional to light flux. Silicon PIN photodiodes all tend to have about the same spectral response curve unless they are specially processed or have a filter added to the detector assembly. They peak around 900 nm at about 0.4 to 0.6 A/W. At visible red expect around 0.3 to 0.4 A/W. See Typical Silicon Photodiode Spectral Response.
Commercial laser power meters cost $300 and up – $1,000 is a more typical price for something that works over a wide range of power levels and wavelengths. Where the precision and automatic wavelength calibration of these instruments is not needed, a basic laser power meter can be built inexpensively. See the section: Sam’s Super Cheap and Dirty Laser Power Meter and those that follow. There are several ways to design a device that will determine the power in a beam of light. Here are two: • Photodiode – each photon within the wavelength range of the device creates an electron-hole pair. When reverse biased, this results in a current flow which is proportional to light flux. Silicon PIN photodiodes all tend to have about the same spectral response curve unless they are specially processed or have a filter added to the detector assembly. They peak around 900 nm at about 0.4 to 0.6 A/W. At visible red expect around 0.3 to 0.4 A/W. See Typical Silicon Photodiode Spectral Response. • Therm
