초록 ▼

Bulk material formed by a multiplicity of individual moving particles is heat-treated by directing a light beam into an observation volume of the material and generating light reflections off at least one particle in the observation volume. A characteristic of the light reflections which is indicati

Bulk material formed by a multiplicity of individual moving particles is heat-treated by directing a light beam into an observation volume of the material and generating light reflections off at least one particle in the observation volume. A characteristic of the light reflections which is indicative of a desired extent to which the material is to be heat-treated is identified and the material is subjected to a heated environment and thereby heat-treated. The light reflections are monitored for the characteristic, and subjecting the material to the heated environment is ended in response to detecting the characteristic of the light reflections.

대표청구항 ▼

[ What is claimed is:] [5.] A method of roasting coffee beans and objectively terminating the roasting in real time at substantially the instant when the beans have reached a desired degree of roasting comprising heating the beans; forming a flow of beans as the beans are being heated; illuminating

[ What is claimed is:] [5.] A method of roasting coffee beans and objectively terminating the roasting in real time at substantially the instant when the beans have reached a desired degree of roasting comprising heating the beans; forming a flow of beans as the beans are being heated; illuminating an observation volume of the flow with laser light of a predetermined wavelength to thereby generate light reflections off the beans in the observation volume; collecting some of the light reflections from the beans in a manner which limits variation in the light reflections to variations caused by changes in a surface characteristic of the beans; establishing a characteristic of the light reflections which is indicative that the beans have been roasted to a desired extent; and terminating roasting when the light reflections substantially exhibit the established characteristic for the light reflections.