EP0391682A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Method for measuring particulate size without contacting the particulate and related apparatus
Assignee: Kanai Educational Institution
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Filing: 1990-04-04
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Granted: —
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Expires: 2010-04-04
Abstract
Abstract A method and related apparatus are described for measuring the size of a particulate, without contacting the particulate, and therefore without extra forces on the particulate. Striped gaps of interference fringes at a plane surface (2) behind the particulate (G) which occur when a monochromatic beam is radiated on a particulate by means of a monochromatic light source (1, 11) are measured and used to derive a measure of the particulate size.
Inventors
- 👤 Kenzo Kanai
- 👤 Norikane Kanai
- 👤 Hiroshi Ito
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 11:38
CPC Classifications
G; G01; G01N; G01N15/00; G01N15/02; G01N15/0205
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
53 words
A method for measuring a size of a particulate without contacting the particulate, comprising the steps of: (a) radiating a monochromatic beam past a particulate; (b) measuring a gap(Δχ) of interference fringes occurring on a plane surface behind the particulate; and (c) obtaining the size of the particulate based on the obtained value(Δχ).
Claim 2
Independent Claim
53 words
A method for measuring a size of a particulate without contacting the particulate, comprising the steps of: (a) radiating a monochromatic beam past a particulate; (b) measuring a gap(Δχ) of interference fringes occurring on a plane surface behind the particulate; and (c) obtaining the size of the particulate based on the obtained value(Δχ).
Claim 3
Dependent Claim
57 words
The method as recited in claim 1, wherein the size of the particulate is obtained using the formula : D = λZ Δχ in which D is the diameter of the particulate ; λ is the wavelength of radiating monochromatic beam ; and Z is the distance between the particulate and a place the gap is measured.
Claim 4
Dependent Claim
25 words
The method according to claim 1, wherein the interference fringes are recorded on film and the gap of interference fringes is measured by a microphotometer.
Claim 5
Dependent Claim
17 words
The method according to Claim 1 or Claim 2, wherein the monochromatic beam is a laser beam.
Claim 6
Independent Claim
79 words
An apparatus for measuring particulate size without contacting the particulate, comprising: (a)means for directing a monochromatic beam on a path; (b)means positioned in the path for recording a pattern of interference fringes occurring in shade portions of the particulate when the monochromatic beam is interupted by the particulate(G) ; (c)means for measuring a gap of recorded interference fringes and outputting a signal representative of the gap; and (d)means for calculating the size of the particulate based on the signal.
Claim 7
Independent Claim
79 words
An apparatus for measuring particulate size without contacting the particulate, comprising: (a)means for directing a monochromatic beam on a path; (b)means positioned in the path for recording a pattern of interference fringes occurring in shade portions of the particulate when the monochromatic beam is interupted by the particulate(G) ; (c)means for measuring a gap of recorded interference fringes and outputting a signal representative of the gap; and (d)means for calculating the size of the particulate based on the signal.
Claim 8
Dependent Claim
16 words
The apparatus according to Claim 4, wherein the beam radiating means is an He-Ne laser generator.
Claim 9
Dependent Claim
24 words
The apparatus according to Claim 4 or Claim 5, wherein the pattern recording means is an optical camera for recording an image on film.
Claim 10
Dependent Claim
48 words
The apparatus according to any of Claim 4,5 or 6, wherein the measuring means is a microphotometer including photoelectric elements, said microphotometer outputting the gap signal as a variation of voltage based on the gap of the interference fringes photographed over the film of the pattern recording means.
Claim 11
Dependent Claim
22 words
The apparatus according to Claim 4 or Claim 5, wherein the pattern recording means is a camera including a CCD image sensor.
Claim 12
Dependent Claim
58 words
The apparatus according to claim 8, wherein the measuring means is an A-D converter, which makes an A-D conversion of the signal of interference fringes photographed by the pattern recording means and outputs a pulse number obtained in proportion to the size of the interference fringes gap as the signal value(Δχ) of the gap signal for the counter.
Claim 13
Dependent Claim
18 words
The apparatus according to any of Claim 4,5,6 7,8 or 9, wherein the calculation means is a microcomputer.
References Cited (Backward Citations)
No citation records indexed.
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