Answer:
Yes, there's a limit
Explanation:
Yes, there's a limit which is set by nλ = 90°, because a transmission grating cannot transmit backwards!
In diffraction gratings, the formula is;
nλ = d sinθ
For the maximum number of orders produced,θ = 90°
Thus;
nλ = d sin(90°)
nλ = d
Hence, nλ < d, or n < d/λ
This will represent the highest order of transmission spectra that is observable.
However, a transmission grating will also be able to produce a reflection spectrum which is generally very dim, and not used much. In this, the orders are numbered from the reflection normal, and also limited to nλ < 90°
