The wavelength in the lens is different, of course, but that is not a change of the wavelength with the usual meaning (= a change in the frequency, and a different wavelength in the same medium).Arian DP said:@mfb : May be there is a relation to the changing of refraction index from lens (rarer medium)to the microstructure(denser medium) so that it can also change the wavelength of light.
Arian DP said:@sophiecentaur: I also got some reference said that the frequency will be constant/not change. But the wavelength and the wave speed change from medium to other medium.
Arian DP said:@sophiecentaur: Yes, I want a color change but not a significant change. In example I want to change a normal blue to a blue sky. Is it still possible?
wikipedia said:The color rendering of RGB LEDs, however, is worse than one would expect; the wavelength gap between red and green is much larger than that between green and blue, resulting in an uneven spectral density. An orange fruit, for example, does reflect some red and it does reflect some green, but not in a ratio that the human retina interprets as orange. Neglecting to poll the orange line makes most orange objects appear reddish. RGB LEDs are therefore suitable for display purposes, but less so for illumination, which prompted some manufacterers to add a fourth, amber LED, marketing the product as RGBA LED (not to be confused with the RGBA color space) or tetrachromatic white LED. It can be expected that the number of colors will be further increased to six or more, equally-tempered wavelengths.
The second method, phosphor converted LEDs (pcLEDs) uses one short-wavelength LED (usually blue, sometimes ultraviolet) in combination with a phosphor which absorbs a portion of the blue light and emits a broader spectrum of white light. (The same mechanism—the Stokes shift—is used in a fluorescent lamp emitting white light from a UV-illuminated phosphor.) The major advantage is the low production cost. The CRI (color rendering index) value can range from less than 70 to over 90, and color temperatures in the range of 2700 K (matching incandescent lamps) up to 7000 K are available. The character of the light cannot be changed dynamically. The phosphor conversion absorbs some energy, but most of the electrical energy is still wasted as heat within the LED chip itself. The low cost and adequate performance makes this the most widely used LED technology for general lighting today.
Arian DP said:@sophiecentaur: Yes, I want a color change but not a significant change. In example I want to change a normal blue to a blue sky. Is it still possible?
A change of light wavelength refers to the phenomenon in which the color of light changes as it travels through different mediums, such as air, water, or glass. This change occurs due to the interaction of light with particles in the medium, causing it to refract or scatter.
A change of light wavelength is caused by the interaction between light and particles in a medium. This interaction can be due to factors such as refraction, scattering, or absorption.
A change of light wavelength can greatly affect the perception of color. For example, when white light passes through a prism, it splits into different wavelengths, creating a rainbow of colors. Similarly, when light passes through a medium, its wavelength can change, resulting in a change in color perception.
The wavelength of light is directly proportional to its energy. This means that shorter wavelengths, such as blue and violet, have higher energy levels compared to longer wavelengths, such as red and orange. This relationship is known as the electromagnetic spectrum.
A change of light wavelength is measured in nanometers (nm). This unit represents the distance between two consecutive peaks or troughs of a wave. The shorter the wavelength, the higher the energy and vice versa.