Diffraction Efficiency Parameter Research Articles

Replication of Holograms with Corn Syrup by Rubbing

Corn syrup films are used to replicate holograms in order to fabricate micro-structural patterns without the toxins commonly found in photosensitive salts and dyes. We use amplitude and relief masks with lithographic techniques and rubbing techniques in order to transfer holographic information to corn syrup material. Holographic diffraction patterns from holographic gratings and computer Fourier holograms fabricated with corn syrup are shown. We measured the diffraction efficiency parameter in order to characterize the film. The versatility of this material for storage information is promising. Holographic gratings achieved a diffraction efficiency of around 8.4% with an amplitude mask and 36% for a relief mask technique. Preliminary results using corn syrup as an emulsion for replicating holograms are also shown in this work.

Corn syrup holograms

A study of the diffraction efficiency parameter, of holographic gratings recorded with thin emulsion layers of corn syrup (Karo®) photosensitized with potassium dichromate salt is presented. This was possible by the interference produced by amplitude division setup using two wavelengths at 473nm and 530nm respectively. The maximum diffraction efficiency for corn syrup with potassium dichromate films was on average in the order of 4.0% at first diffraction order. The energy that was applied at blue light was 10 times less than that applied at green light.Evolution in the behavior profile from the diffraction efficiency parameter is presented as a function of relaxation time necessary to obtain major performance of these gratings made with peculiar sweetener.Holograms with this material do not require developing processes, because these samples develop by themselves. After of exposition with light laser, is necessary wait to stabilize the material 96h, to protect the film against the environmental humidity.

Holograms in polyvinyl alcohol photosensitized with CuCl<sub>2</sub>(2H<sub>2</sub>O)

We propose the use of polyvinyl alcohol photosensitized with copper chloride dihydrated CuCl2(2H2O) as a photosensitive material for recording holographic gratings. We obtained different dissolutions changing concentration of photosensitive agent and varying their pH factor, refraction index, and optical density for each sample. We registered diffraction gratings by holographic methods. The behaviors of diffraction efficiency parameters of holographic gratings regarding the concentration of a photosensitive agent were analyzed. We show there exists a correspondence between the diffraction efficiency parameter with concentration change of CuCl2(2H2O). The low toxicity of this holographic recording material as well as its peculiar behavior, photosensitivity, and ability to conduct electricity, makes it attractive for production diffractive optical elements with bio-polymers.

Holograms preparation using commercial fluorescent benzyl

We have been able to make holograms with substances such as fluorescence thought of light blue laser to make transmissions holograms, using ammonium dichromate as photo-sensitizer and polyvinyl alcohol (PVA) as matrix. Ammonium dichromate inhibit the fluorescence properties of inks, both mixed in a (PVA) matrix, but we avoid this chemical reaction and we show the results to use the method of painting hologram with fluorescents ink and we describe how the diffraction efficiency parameter changes as a function of the ink absorbed by the emulsion recorded with the gratings, we got good results, making holographic gratings with a blue light from laser diode 470 nm. And we later were painting with fluorescent ink, integrating fluorescence characteristics to the hologram.

UHU ® adhesive holograms replication

It is possible to apply a new recording material with high diffraction efficiency (of the order of 82.3%) to replicate computer phase or analogical holograms. This material is the all purpose adhesive UHU ®. It is constituted by some components of polyvinyl, nitrates and some solvent agents; it is easily applied to any substrate. We record this material with heat generation by hand rubbing, using a mask (Kodalith ® films) manufactured with lithographic techniques. The holographic replication is excellent on the new material UHU ® adhesive, showing a phase modulation for refraction index and relief. This modulation is determined by the cured polymers process induced by friction, as pressure and temperature, with an anaerobic reaction. For copy of conventional holograms at high frequencies (holographic ranges), the diffraction efficiency parameter is in the neighborhood of 19.1% at first order or more, depending on diffraction efficiency of the pattern of the hologram. The hologram is elaborated in the absence of any development process and does not need to have carefully controlled conditions of the environment. Following this process, the hologram is obtained at standard atmospheric conditions of pressure and temperature.

Duplication of holograms by using fingernail polish

In this manuscript, we report the results of a research effort in finding an innovative recorder material which utilized fingernail polish (Super Oro One Coat®) information by means of the control of temperature as a parameter induced by hand rubbing. Analogical and computer holograms were replicated, resulting in a high quality behavior of fingernail polish through coating the polish with an average thickness of 10–15μm, which contains some components of polyester resin with nitrocellulose. Through this material we obtained a high absolute diffraction efficiency, which was approximately equal to 90%, with gratings of 100lines/mm. For a copy of conventional holograms at high frequencies (holographic ranges) the diffraction efficiency parameter is in the neighborhood of 22% at first order or more, depending on diffraction efficiency of the pattern of the hologram. The hologram is elaborated in the absence of any development of any process and does not need to have carefully controlled environmental conditions. Following this process, the hologram is obtained at standard atmospheric conditions of pressure and temperature. Another advantage is that it is possible to obtain a hologram at a lower cost; furthermore, the property of applicability to any substrate that it has is remarkable.