The IG19 is a new x-InGaAs photodiode with a peak wavelength at 1.75 μm. Thus, it is ideal for applications that cannot be fulfilled spectrally with a regular InGaAs photodiode. The IG19X1000S4i with a 1 mm chip diameter in a TO-46 housing is the standard product.
IA35 describes a heterostructure photodiode on an InAs substrate with a relatively wide peak at 2.8 μm. The curve of the spectral response can be seen in the figure.
The IA35S500S4i is available. This detector with a 0.5 mm chip is designed especially for uncooled operation and a spectral range of up to 3.5 μm (20% cut-off).
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