Principle and composition of dimming film
The principle and composition of frequency doubling lenses in laser accessories. Frequency doubling lenses can convert various invisible infrared beams into visible light, effectively detecting, tracking, calibrating, and identifying infrared beams. They are used in various fields such as near-infrared light detection of semiconductor lasers, tracking of infrared light-emitting diode emission light, calibration of YAG and other large laser beams, and detection of fiber optic communication signals.
The infrared detection board is made of upconversion luminescent materials, which can be powder, ceramic, or glass blocks. It can be lit up using a 0.3mW red light source, and the effective light excitation band is mainly between 700 nanometers and 10 microns. The same detection board can recognize infrared lasers in different bands, and the luminous intensity is proportional to the excitation power of the infrared device. The products include cardboard, plastic, glass, metal, and ceramic lamps, and their area, shape, size, and color can be customized according to user requirements for special functions. Alternatively, we sincerely provide conversion plates and do not need non-linear optics. Its essence is two-photon absorption, which means absorbing two photons and emitting one photon. If a material has three energy levels with equal spacing, absorbs a photon from level 1 to level 2, and then absorbs another photon from level 2 to level 3, then if the photon is generated and directly transitions from level 3 to level 1, it achieves the function of doubling the frequency.
The so-called frequency doubling is an optical nonlinear effect, which is just a special case of optical mixing. Other common ones include sum frequency, difference frequency, third harmonic, fourth harmonic, etc.
Usually, some nonlinear crystals (such as KDP, KTP, etc.) are used to achieve frequency conversion. The most commonly encountered method, such as green semiconductor lasers, is achieved through frequency doubling.
The optical nonlinear effect is the strong light effect. That is to say, it is difficult to observe under typical weak light and low energy density conditions.
In principle, a simple understanding is that if the stimulated absorption process of a normal laser absorbs one photon with energy of hv1 and radiates 1hv1 laser, then frequency doubling means simultaneously absorbing two photons with energy of hv1 and radiating one laser with energy of hv2. Here v2=2 * v1. This creates a multiplier effect.
Now it's easy to understand the conversion film. Infrared light cannot be directly seen by the human eye, but if the doubled frequency falls within the visible light range, it can be directly observed by the human eye.
Ruicheng Optoelectronic Technology Co., Ltd. is a professional manufacturer of optical solutions, including optical lenses, optical lenses, and optical coatings. Our main products include narrowband filters, bandpass filters, long short wave filters, spectrometers, combiners, dichroic mirrors, reflectors, protective mirrors, focusing mirrors, dimming mirrors, galvanometers, field mirrors, lenses, prisms, laser cutting machine lenses, laser welding machine lenses, laser beauty equipment lenses, OPT beauty waveplates, laser protective lenses, medical equipment lenses, lighting fixtures lenses, stage lighting lenses, four-wheel alignment instrument lenses, laser rangefinder lenses, smoke meter measuring instrument lenses, drone polarizers, security camera lenses, police equipment filters, multi band criminal investigation filters, enzyme-linked immunosorbent assay (ELISA) instrument filters, spectrophotometer detection equipment filters, ultraviolet narrowband filters, etc