91影视

As the intensity increases, the diffraction maximum becomes narrower as well as more intense. When you have 600 slits, the maxima are very sharp and bright and permit high-resolution separation of the maxima for different wavelengths. Such a multiple-slit is called a diffraction grating.

In single slit diffraction,

Intensity is given as $I=I_m\frac{{\text{sin}}^2伪}{{伪}^2}$

Differentiating the above with respect to a ,

$\frac{dI}{d伪}=2I_m\frac{\sin 伪}{{伪}^3}\left(伪\cos 伪-\text{sin}伪鈥�\right)$

For maxima and minima$\frac{dI}{d伪}=0$

So either

$伪=0$or $\text{sin}伪=0$or $伪\cos 伪-\text{sin}伪=0$

But $伪=0$so $\text{sin}伪=0$

So $伪=m蟺$

Again, if $伪\cos 伪-\text{sin}伪=0$

Or $\tan 伪=伪$

Since ${\left(\frac{d^{2}I}{d{伪}^2}\right)}_{伪=\tan 伪}=negative$

There is a maxima at $\tan 伪=伪$.

Let $y=\tan 伪$ where $y=伪$

From the graph,

The smallest value of $伪=0$.

Hence, the value is$伪=0$.

As,$\tan 伪=伪$,

localid="1664272360306" $伪=\left(m+\frac{1}{2}\right)蟺$

For central maximum, $伪=0$

Hence, the value is $\left(m=-\frac{1}{2}\right)$

The second smallest $伪=4.493rad$

Hence, the value is$伪=4.493rad$.

Associated $\left(m\right)=\frac{a}{蟺}-\frac{1}{2}$

$\left(m\right)=0.93$

Hence, the value is $\left(m\right)=0.93$

The third smallest $\left(a\right)=7.725rad$

Hence, the value is $\left(a\right)=7.725rad$

Associated $\left(m\right)=\frac{a}{蟺}-\frac{1}{2}$

$\left(m\right)=1.96$

Hence, the value is $\left(m\right)=1.96$