halide crystal การใช้

• Inside the photographic emulsion are millions of light-sensitive silver halide crystals.
• In black-and-white photographic film there is usually one layer of silver halide crystals.
• Agent 1 is the developer that reduces the silver halide crystals.
• At very low light levels, grains, usually silver halide crystals.
• A "'sensitivity speck "'is a place in silver halide crystal where latent image is preferentially formed.
• If it hits photographic film, it will darken at most one of the silver halide crystals.
• Film is basically a lot of silver halide crystals suspended in gelatin on a plastic backing.
• However, again, the developer potential must be well below the conduction band of silver halide crystal.
• Depending on the silver halide crystal, the latent image may be formed inside or outside of the crystal.
• In such a case, many of the photoelectrons will recombine with the silver halide crystal and be wasted.
• When the exposed silver-halide crystal is developed, it is coupled with a dye grain of its complementary color.
• This is called fog, which is metallic silver made from non-imagewise ( exposure-nonspecific ) reduction of silver halide crystals.
• Finally, hydrogen is a chemical reducing agent, which'seeds'the dry, de-oxygenated silver halide crystal with a few atoms of silver.
• But the first step _ light striking a silver halide crystal and creating silver atoms _ is always the same.
• When a photon is absorbed by a silver halide crystal, a free-carrier ( electron in the conduction band ) is generated.
• In a suitably formulated developer, electrons are injected to the silver halide crystals only through silver speck ( latent image ).
• This kind of fog does not require a fog centre in each silver halide crystal, since they can grow on other substrates other than photosensitive silver halide crystals.
• Modern preparation of a simple, light-sensitive surface involves forming an emulsion of silver halide crystals in a gelatine, which is then coated onto a film or other support.
• These agents have stronger reduction potentials than those of Agent 1 group, but they have very poor adsorption on silver halide crystals, due to lack of argentophilic end.
• This kind of fog does not require a fog centre in each silver halide crystal, since they can grow on other substrates other than photosensitive silver halide crystals.