A holographic filter is a special type of optical filter that uses the principles of holography to selectively transmit light based on its wavelength or color. Holographic filters are usually thin films that have been exposed to a two-beam interference pattern. These filters work by diffracting incoming light, changing its direction to create a separation of colors - this is what produces the holographic effect we commonly associate with prisms and rainbows.
Here are some common uses of holographic filters:
- Photography: Holographic filters are frequently used in photography and cinematography to add a creative, colorful flair to images and scenes. They can be used to add unique visual effects, such as rainbows, starburst effects, or other color distortions.
- Spectroscopy: In the scientific field, holographic filters are critical for precise measurements of light and its properties. They are used in spectrophotometers and other instruments to isolate individual wavelengths of light for study.
- Display technology: Holographic filters have significant potential in next-generation display technologies, including VR/AR applications. They could potentially enable slimmer, lighter displays that still offer high brightness and color accuracy.
- Security and authentication: Holographic filters are often used on credit cards, IDs, and product packaging to provide a visible indication of authenticity. The unique visual effects of a hologram are difficult to forge, providing a simple, reliable way to check for counterfeits.
Learn more:
- OSA | High-efficiency transmissive Holographic Optical Element for Augmented Reality
- US8749933B2 - Holographic iridescence prevention filters
- Selfie Ring Light med Holographic Filter