Camera lenses (n=1.4) are often coated with a thin film of magnesium fluoride (n = 1.26). These non-reflective coatings use destructive interference to reduce unwanted reflections. Find the condition for destructive interference in this case, and calculate the minimum thickness required to give destructive interference for light in the middle of the visible spectrum (yellow-green light, air = 560 nm). Number Units Correct response: 111.111111 nm ± 5.0%

What is the spacing between structures in a feather that acts as a reflection grating, giving that they produce a first-order maximum for 525-nm light at a 30.0° angle?

Sophisticated cameras use a series of several lenses. Light can reflect from the surfaces of these various lenses anddegrade image clarity. To limit these reflections, lenses are coated with a thin layer of magnesium fluoride that causesdestructive thin film interference. What is the thinnest this film can be, if its index of refraction is 1.38 and it is designed tolimit the reflection of 550-nm light, normally the most intense visible wavelength? The index of refraction of glass is 1.52.

A He-Ne gas laser which produces monochromatic light of a known wavelength ? =6.35 ? 10^7 ? is used to calibrate a reflection grating in a spectroscope. The first-order diffraction line is found at an angle of 22 degrees to the incident beam. How many lines per meter are there on the grating?

The limit to the eye’s acuity is actually related to diffraction by the pupil. What is the angle between two just-resolvable points of light for a 3.00-mm-diameter pupil, assuming an average wavelength of 550 nm?

Two point sources of light are separated by 5.5 cm a. As viewed through a 13 μmμm diameter pinhole, what is the maximum distance from which they can be resolved if red light ( λλ = 690 nmnm) is used? b. If violet light ( λλ = 420 nmnm ) is used?

What is the smallest thickness & of an optical coating whose designed ndx of refraction is n coating = 1.38 and which is to eliminate reflected light at wave lengths around 550 nm when incident normally on glass for which nglass=-1.50 [hint= Incident ray will first go through coating layer and then the glass layer.

A He-Ne gas laser which produces monochromatic light of a known wavelength a = 6.35 x 10-7 m is used to calibrate a reflection grating in a spectroscope. The first-order diffraction line is found at an angle of 22° to the incident beam. How many lines per meter are there on the grating?

3. a) Calculate the reflectance of a quarter-wave anti-reflecting film of magnesium fluoride (n = 1.35) coated on an optical glass surface of index 1.52. b) Calculate the peak reflectance of a high-reflecting multilayer film consisting of N = 4 stacks of coating materials with high-low refractive index (nH = 2.8 and n, = 1.4).

White light is incident normally on a glass lens (n=1.52) that is coated with a film of MgF2(n=1.38). For what minimum thickness of the film will the reflections at the two interfacesresult in total destructive interference of yellow light of wavelength 580 nm (in air)?