Scanning apparatus and method

• US 4,118,730 A
• Filed: 05/18/1972
• Issued: 10/03/1978
• Est. Priority Date: 03/11/1963
• Status: Expired due to Term

• Current Assignee: Jerome H. Lemelson
• Original Assignee: Jerome H. Lemelson
• Inventors: Lemelson, Jerome H.
• Primary Examiner(s): Britton, Howard W.
• Application Number:
  US05/254,710
• Time in Patent Office: 2,329 Days
• Field of Search: 178/6.8, 178/DIG. 1, 178/DIG. 33, 178/DIG. 36, 178/DIG. 37, 178/DIG. 38, 178/DIG. 6, 328/111, 328/129, 358/93, 358/105, 358/106, 358/107, 360/38
• US Class Current: 348/94
• CPC Class Codes: B07C 5/10 measured by light-responsive means sorting according to colour B07C5/342
• CPC Class Codes: G07D 7/12 Visible light, infrared or ultraviolet radiation
• CPC Class Codes: G08B 13/19602 Image analysis to detect motion of the intruder, e.g. by frame subtraction
• CPC Class Codes: G08B 13/1963 Arrangements allowing camera rotation to change view, e.g. pivoting camera, pan-tilt and zoom [PTZ]
• CPC Class Codes: G08B 13/19634 Electrical details of the system, e.g. component blocks for carrying out specific functions
• CPC Class Codes: G08B 13/19652 Systems using zones in a single scene defined for different treatment, e.g. outer zone gives pre-alarm, inner zone gives alarm

Abstract

An automatic scanning and control apparatus determines the location of a predetermined segment of an image field being scanned. The predetermined segment presents an image which is optically differentiatable from the surrounding area of the image field. The apparatus includes a beam device for selectively scanning the image field and producing an output signal thereof. The beam device includes means for modulating the output signal in accordance with variations in the image field. The predetermined segment of the image field causes modulation of the output signal of the beam device by providing an inflection therein when the beam scans across the segment. An analyzing circuit is adapted to accept the output signal from the beam device. Means generate a locating signal in predetermined time relation to the scanning. Comparator means compare the inflection in the output signal with the locating signal so that the location of the predetermined segment of the image field can be determined.

A method compares an image field to be inspected with a standard image field. A standard image field is scanned with a beam and a video signal is modulated in accordance with intensity variations in the standard field. The video signal is recorded on a recording member. The field to be inspected is then scanned by the beam and a second video signal is generated. Both the video signals are reproduced and passed to a comparator means. A point to point comparison is made between the inflections and variations in each signal resulting from the scanning image areas of contrasting intensity of generating pulse signals during the intervals that the areas do not coincide. The pulse signals are then automatically analyzed.

Claims

1. An automatic inspection apparatus for determining the location of a selected image in an image field whereby said selected image is optically differentiatable from the surrounding area of the image field, said apparatus comprising:

(a) a beam device,

(b) means for moving the beam of said device for line scanning said image field,

(c) means for generating an output signal on said line scanning means,

(d) means for modulating said output signal in accordance with variations in the image field scanned by the beam of said beam device,

(e) means for causing the beam of said beam device to scan said selected image and to be modulated in response to radiation from said selected image,

(f) means for providing an inflection in said outputs signal when said beam scans across said selected image, and

(g) an analyzing circuit operable to receive said output signal,

(h) said analyzing circuit including means for generating a code responsive to said inflection in said output signal,

(i) said generated code being indicative of said selected image in the image field scanned.

2. An automatic scanning apparatus for determining the characteristic of a segment of an image scanned, which segment is optically contrasting from adjacent portions of the field, said apparatus comprising:

(a) a beam device for line scanning an image and producing an information signal of the image scanned,

(b) circuit means for producing a first signal when said beam device commences scanning said optically contrasting segment of said image,

(c) signal generating means for generating a comparison signal in synchronized time relation to the beam scanning operation,

(d) means for comparing the characteristics of said comparison signal with that portion of said information signal generated in scanning said predetermined segment of the image field being scanned.

3. An inspection apparatus comprising:

(a) an electro-optical device for selectively scanning an image field and producing a picture signal representative of the optical characteristics of the area scanned,

(b) an image field having an image defining portions of said field, which image is optically contrasting with respect to surrounding image areas,

(c) said electro-optical device including means for producing an output signal and modulating said output signal in accordance with variations in the image field scanned,

(d) whereby inflections occur in said output signal which inflections are representative of the characteristics of said optically contrasting image areas,

(e) a digital code generating means coupled to said device and adapted to be energized when inflections occur in said output signal, and

(f) means operatively connected to said digital code generating means for receiving and utilizing signals generated thereby and to discriminate the same whereby the characteristics of said predetermined segment of said image field can be determined.

4. An apparatus as defined in claim 3 wherein

said electro-optical device includes means to scan a plurality of optically contrasting images in an image field,

said digital code receiving means including means for summing the digital codes generated by said digital code generating means.

5. An apparatus as defined in claim 3 wherein

said digital code generating means is adapted to generate codes indicative of the dimensions of images in the field scanned.

6. In a surface inspection system for material in which flaws have a different optical appearance than the remainder of the material, the combination comprising:

(a) an electro-optical device for scanning an image of said material and operable to produce a video signal and a pulse each time the device scans the image of a flaw in said material,

(b) circuit means responsive to said video signal for producing a differentiated signal including a pair of spiked pulses respectively at the leading and trailing edges of the images of the flaws scanned,

(c) said circuit means including means for determining the extent of said flaws and timing means operatively connected to said spiked pulse producing means to compute the total time between pairs of spiked pulses over a given time interval.

7. An automatic scanning system comprising:

(a) a conveyor for handling a plurality of articles to be inspected,

(b) an electro-optical scanning means disposed adjacent said conveyor for scanning a field through which individual articles move as carried by said conveyor,

(c) detection means for detecting the presence of an article at said inspection station,

(d) means for aligning articles in said field as they pass said inspection system,

(e) control means for controlling said scanning means to scan its field,

(f) said scanning means being operable to generate an output signal in accordance with variations in the field scanned, and

(g) analyzing means for receiving and discriminating said output signal whereby the characteristics of an article scanned can be determined.

8. An automatic scanning system as defined in claim 7 wherein

said electro-optical scanning means includes an X-ray beam scanning device.

9. An automatic scanning system as defined in claim 7 wherein

said electro-optical scanning means includes a beam scanning device operative to scan while an article is in motion along said conveying means and in its scanning field.

10. In an apparatus for detecting defects on the surface of moving material in which the defects have a different optical appearance than the remainder of the material, the combination comprising:

(a) an electro-optical beam scanning device for full frame scanning an image of the surface of said moving material with an electron beam,

(b) said beam being adapted to scan substantially perpendicular to the direction of movement of the material,

(c) said beam scanning device being adapted to produce an output signal,

(d) means for receiving the output signal of the electro-optical scanning device and generating a pulsed signal in which a pulse is produced each time the electron beam scans a defect,

(e) means for digitizing said pulse signals, and

(f) means for operating on the digitized pulse signals to obtain an indication of the areas of the defects scanned.

11. An automatic measurement apparatus comprising:

(a) first means for scanning a standard image field and generating a first video signal of said scanning which varies in accordance with variations in said image field,

(b) means for recording said first video signal,

(c) second means for scanning an image field to be analyzed and generating a second video signal which varies in accordance with variations in said second image field,

(d) comparison circuit means for comparing predetermined portions of said video signals, and

(e) means for presenting both said video signals to said comparison circuit means so that the variations in predetermined portions of said signals may be compared.

12. An automatic measurement apparatus as defined in claim 11 wherein

each said video signal is a composite signal including frame vertical sync pulses,

means are provided for reproducing the recorded vertical sync pulse from said composite signals and generating said sync pulses separately from the recorded video signal,

said means for scanning said image field to be analyzed comprising video camera means,

pulse operated trigger means are provided for initiating an image field scanning cycle for said camera means, and

means is provided for applying a separately reproduced vertical sync pulse to said pulse operated trigger means so as to initiate scanning said image field and to generate a picture signal of the scanned field together with the generation of the first video signal generated in scanning the standard image field.

13. A method of comparing an image field to be inspected with a standard image field comprising the steps of:

(a) electro-optically scanning said standard image field and generating a first video signal modulated in accordance with intensity variations in said standard field,

(b) recording said first video signal on a recording member,

(c) electro-optically scanning the field to be inspected and generating a second video signal,

(d) reproducing said first video signal from said recording member,

(e) simultaneously passing said reproduced first video signal and said second video signal to an analyzing circuit, and

(f) comparing inflections and variations in each video signal and generating pulse signals indicative of the extent of variations in said standard image field and the scanned field.

14. A method as defined in claim 13 including:

digitizing said pulse signals to generate code signals which are indicative of the locations of the variations in said scanned and standard fields.

15. A method as defined in claim 14 including

summing at least certain of said code signals to determine the degree of variation of at least one area of said scanned field from an area in said standard field.

16. A method of inspecting an image field capable of exhibiting changes in its characteristics with respect to time comprising the steps of:

(a) first electro-optically scanning said field,

(b) generating a first video signal which is modulated in accordance with variations in the field being scanned,

(c) recording said first video signal on a recording member,

(d) reproducing said video signal from said recording member while simultaneously again scanning said image field at a later time,

(e) generating a second video signal,

(f) comparing at least portions of each of said output signals, and

(g) electrically determining variations in said second video signal from said first video signal.

17. An apparatus for analyzing time variable electrical signals comprising:

(a) first means for generating a time variable electrical analog signal representative of information defined by an image field to be analyzed,

(b) second means for receiving and analyzing said analog signal,

(c) said second means including means for separating those portions of the analog signal having characteristics varying beyond a predetermined minimum value and for selectively gating said separate signal portions to said receiving and analyzing means,

(d) said analyzing means including means responsive to variations in said separated signal portions for digitizing same, and

(e) said digitizing means including means for generating a plurality of digital code signals which are indicative of the value of the variations in said electrical analog signal.

18. An apparatus as defined in claim 17 wherein

said image field is determined by a scanning means.

19. An automatic inspection apparatus comprising:

(a) means for supporting and positioning an object to be inspected at an inspection work station,

(b) radiation beam scanning means disposed at said inspection work station for examining objects to be inspected,

(c) said scanning means including receiving means for the radiation modulated in scanning a portion of the object which varies in physical characteristics and being operable for generating analog information signals that are representative of variations in the physical characteristics of the object under inspection,

(d) means for effecting relative movement between the object and said radiation beam scanning means so as to present different portions of the object in the field scanned by the radiation beam scanning means, and

(e) automatic analyzing means operable for accepting the analog information signals generated by said receiving means,

(f) said automatic analyzing means including analyzing circuit means operable to analyze the information content of said analog information signals.

20. An automatic inspection apparatus as defined in claim 19 including

means for digitizing said analog information signals and generating a plurality of pulse code signals,

said pulse code signals being digital representations of the characteristics of the object scanned by said radiation beam.

21. An automatic inspection apparatus as defined in claim 19 wherein

said analyzing circuit means includes means for digitizing the analog information signals sensed thereby.

22. An automatic inspection apparatus as defined in claim 19 wherein

said automatic analyzing means includes means responsive to the digitized analog information generated by said digitizing means and being operable for performing computations with said digital information thereby producing computational results which are representative of specific characteristics of the object under inspection.

23. An automatic inspection apparatus comprising:

(a) means for supporting and positioning an object to be inspected at an inspection work station,

(b) radiation beam scanning means disposed at said inspection work station for examining objects to be inspected,

(c) means for scanning a selected portion of the surface of said object with said radiation beam scanning means by causing the beam of said scanning means to effect a scanning sweep of the surface of said select portion,

(d) said scanning means including receiving means for the radiation modulated in scanning said selected portion which varies in physical characteristics and being operable for generating analog information signals that are representative of variations in the physical characteristics of the object under inspection,

(e) means for effecting relative movement between the object and said radiation beam scanning means so as to present different portions of the object in the field scanned by the radiation beam scanning means, and

(f) automatic analyzing means operable for accepting the analog information signals generated by said receiving means,

(g) said automatic analyzing means including analyzing circuit means operable to analyze the information content of said analog information signals.