WO1989001643A1 - Appareil d'optique avec dispositif de protection - Google Patents

Appareil d'optique avec dispositif de protection Download PDF

Info

Publication number
WO1989001643A1
WO1989001643A1 PCT/EP1988/000405 EP8800405W WO8901643A1 WO 1989001643 A1 WO1989001643 A1 WO 1989001643A1 EP 8800405 W EP8800405 W EP 8800405W WO 8901643 A1 WO8901643 A1 WO 8901643A1
Authority
WO
WIPO (PCT)
Prior art keywords
protection
sections
light beam
protection device
receiver
Prior art date
Application number
PCT/EP1988/000405
Other languages
English (en)
Inventor
Mario Possati
Original Assignee
Marposs Società per Azioni
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Marposs Società per Azioni filed Critical Marposs Società per Azioni
Publication of WO1989001643A1 publication Critical patent/WO1989001643A1/fr

Links

Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
    • G02B27/0006—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00 with means to keep optical surfaces clean, e.g. by preventing or removing dirt, stains, contamination, condensation

Definitions

  • the invention relates to an optical apparatus com ⁇ prising at least an optical system with a surface arranged in the path of a light beam and a protection device with protection means adapted for being placed in front of the surface for defining a wall that prevents any foreign materials from reaching the surface, and actuation means for displacing the protection means.
  • the invention also relates to an optical apparatus comprising at least one optical system with a surface arranged in the path of a light beam, an opto-electronic image receiver system, electronic processing and diagnosis means connected to the opto-electronic receiver system, a protection device with protection means adapted to be arranged in front of said surface for defining a wall that prevents foreign materials from reaching the surface, and actuation means for displacing the protection means.
  • the invention relates to an optical apparatus comprising an emitter device emitting a beam of light, with a first window for the passage of the light beam; an opto-electronic receiver device having a second window arranged in the path of the light beam; electronic processing and sensing means connected to the receiver device; a first protection device associated to the emitter device and a second protection device associated to the receiver device, the protection devices having protection means placed in front of the first and the second window for protecting them from foreign materials.
  • DE-C1-3203076 refers to a gas laser comprising a transversal cavity resonator with mirrors at the two ends and shutter doors for protecting the mirrors during the start up phase of the laser.
  • the doors automatically open depending on signals provided by pressure indicator devices, to put into optical communication the two mirrors.
  • an optical apparatus comprises at least an optical system with a surface arranged in the path of a light beam, a protection device with protection means adapted for being placed in front of the surface to define a plurality of substantially transparent sections, each of which defines a wall adapted to prevent any foreign materials from reaching the surface, and actuation means adapted to displace the protection means for bringing subsequent ones of the sections in front of the surface.
  • the means for actuating the protection device can be motorized, with a manual control or an automatic one if the optical apparatus is provided with a sensing system for detecting the presence of dirt.
  • Figure 1 is a plan view of an opto-electronic apparatus for checking the diameter of pieces, comprising two optical emitters and two optical receivers, each of which is provided with a protection device;
  • Figure 2 shows a protection device, in a vertical cross-section taken along the plane identified by path II-II in figure 3, applied to an emitter or receiver of the apparatus shown in figure 1;
  • Figure 3 shows the device illustrated in figure 2, in a horizontal section along the plane identified by path III-III in figure 2, applied to the emitter or receiver also shown in figure 2;
  • Figure 4 is a partially sectioned front view of the protection device shown in figures 2 and 3;
  • Figure 5 is a block diagram of part of the circuits and devices for detecting, processing, driving and controlling the apparatus shown in the previous figures; and Figure 6 shows three possible trends of the output signal of a photodiode linear array of an opto-electronic receiver of the apparatus shown in the previous figures.
  • the apparatus illustrated in a very schematical way in figure 1, comprises two optical emitters 1, 2 coupled to a base 3 by means of support elements, that are not shown in figure 1 while one of them - indicated by reference number 4 - is shown in figures 2 and 3.
  • Each optical emitter 1 and 2 comprises a source of monocromatic incoherent light, consisting of a light emitting diode (LED) that emits infrared light, and a collimator.
  • LED light emitting diode
  • the collimated beam of light is directed in a longitudinal direction with respect to base 3 and is partially intercepted by the edge of a circular cross-section of workpiece 5, positioned on base 3 in a fixed way or with the possibility of rotating about its
  • receivers 6, 7 are coupled to base 3 by means of support elements, like element 4, partially shown in figures 2 and 3, which is C-shaped and supports both receiver 6 and emitter 1 - in a way that is not shown in the figures - so fixing their mutual position.
  • Each of receivers 6, 7 comprises a sealed casing housing a system of convergent lenses, a spatial filter and a linear array of photodiodes on which the image of the edge of workpiece 5 is formed.
  • Emitters 1, 2 and receivers 6, 7 have windows comprising plane plates of optical glass 8, 9, 10 and 11.
  • the spatial position of the images of the edges of workpiece 5 with respect to the arrays of diodes of receivers 6 and 7 is determined by means of electronic scanning circuits and since the distance between the receivers is known, the measurement of the workpiece diameter is obtained.
  • Protection devices 12, 13, 14, 15, one of which - 13 - is now described with reference to figures 2 to 4, are coupled to emitters 1, 2 and receivers 6 and 7 in correspondence to the glass plates 8, 9, 10 and 11.
  • Protection device 13 is essentially a cartridge with a plastic casing 16 that houses two rollers 17, 18, the first driven and the second driving. Roller 17 is idle onto a pin 19 integral to casing 16 while driving roller 18 is keyed onto a pin 20 rotatably arranged within casing 16.
  • rollers 17 and 18 there is wound a flexible tape or film 21 made of polycarbonate polymer, that has good optical properties (more specifically, it is extremely transparent) and good mechanical properties (high resistance to scorings) .
  • the tape reaches roller 18 by passing through a guide gap 22 defined between a front cover 23 and a front plane face 24 of casing 16.
  • the central part of guide gap 22 is delimited by plane surfaces of two lateral sections 25 and 26 of cover 23, and of casing 16.
  • Casing 16 has a through opening 27 arranged between tape 21 and glass plate 9. At the end of guide gap 22 adjacent to an edge of through opening 27 there is a seal gasket 28 that prevents dust and other foreign materials from entering through gap 22 and towards roller 17.
  • Tape 21 reaches roller 18 by passing through another guide gap 29 formed in casing 16.
  • Casing 16 has a cylindrical seat 30 with a base 31 where is formed opening 27.
  • seat 30 there are also formed an annular shoulder 32 for cooperating with an end of receiver 6 and an annular groove 33 for the insertion of an elastic ring 34.
  • the protection device 13 is inserted onto the cylindrical casing of receiver 6, the diameter of which is slightly smaller than that of cylindrical seat 30.
  • the coupling stability is guaranteed by elastic ring 34 and by possible projections and associated guide grooves foreseen in the receiver casing and in cylindrical seat 30.
  • motor 35 having a shaft 36 carrying at an end a bevel gear 37 that engages with another bevel gear 38 mounted onto a shaft 39 coupled to pin 20.
  • motors and gears similar to those of figures 2, 3 and 4 are associated to the other protection devices 12, 14 and 15 even though, for simplicity's sake, this is not illustrated in figure 1.
  • motor 41 associated to the protection device 12 of transmitter 1
  • motor 35 associated to the protection device 13 of receiver 6
  • some functional blocks of a power supply, detecting, processing, driving and control unit 42 shown in figure 1).
  • An internal bus 43 is connected to a central processing unit (CPU) 44, a card 45 for driving motors 35 and 41 and an interface 46.
  • CPU central processing unit
  • Interface 46 is connected to a circuit 47 for controlling the diode array of receiver 6.
  • Circuit 47 is also connected to emitter 1.
  • the single photodiodes of the array of receiver 6 provide an output voltage signal having an amplitude depending, apart from the intensity of the light beam emitter by emitter 1, on the emitter 1-receiver 6 distance, the darkening due to the presence of workpiece 5 and the presence of dirt along the path of the light beam from emitter 1 to the diode array of receiver 6.
  • Figure 6A shows the transition of the voltage signal from value V_, that corresponds to photodiodes not receiving light owing to the presence of workpiece 5, to value V , provided by fully illuminated photodiodes.
  • the photodiodes are obviously in a discrete number, but as their mutual distance is in the order of micrometers, the transition zone normally includes many photodiodes. Consequently, for simplicity's sake, the voltage values relating to the photodiode array segment D-D' corresponding to the transition due to the edge of workpiece 5 are shown in figures 6A, 6B and 6C with a continuous line.
  • Figure 6A relates to normal conditions.
  • Figures 6B and 6C relate to abnormal conditions due to the presence of dirt that attenuates the signal in the transition area
  • Unit 42 is programmed in such a way that central unit 44 processes the signals received through circuit 47 and interface 46 in order to carry out measurements and also accomplish a diagnosis function, i.e. to detect an irregular trend of the output signal of the photodiode array of receiver 6. This can occur on the basis of different algorithms, for example on the basis of the deviations of the single voltages from the values V M and V Q , the detection of the derivative of the signal represented by the curves shown in figure 6, etc.
  • unit 42 detects anomalies, a signal reaches card 45 and commands motors 35 and 41, to make a forward step in such a way that (as far as the protection device 13 is concerned) roller 18 rotates and tape 21 is advanced by an amount that is slightly greater than the height of through opening 27.
  • glass plate 9 i.e. the window of receiver 6 (and similarly the equivalent windows of emitters 1, 2 and of receiver 5) , is protected against dirt by a section of tape 21 and if said section of tape and/or the section of tape placed in front of the window of emitter 1 become dirty, this is automatically detected and, again in an automatic way, the motorized actuation means (comprising motors 35 and 41) are actuated to bring a fresh, clean section of the protection means
  • each part or section of the protection means defines a transparent wall that protects the windows.
  • the planarity error can be kept within the tolerance limits thanks to the central part of guide gap 22; to this purpose, the lateral sections 25 and 26 can be very close to face 24 of casing 16 and be made to produce a slight resilient pressure that keeps tape 21 into contact with the reference surface consisting in face 24.
  • the thickness of tape 21 can be selected within the range 0. 01 to 0. 1 mm.
  • a corresponding monitoring and alarm device 50 can be foreseen in unit 42.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Length Measuring Devices By Optical Means (AREA)

Abstract

Appareil d'optique muni d'une ouverture (9) disposée sur la trajectoire d'un rayon lumineux et dispositif de protection (13) destiné à empêcher la poussière et d'autres corps étrangers de se déposer sur l'ouverture (9). Afin de réduire l'entretien tout en assurant un bon fonctionnement de l'appareil, le dispositif de protection (13) comporte une bande transparente (21) mue par un moteur (35) qui amène l'une après l'autre les différentes parties de la bande (21) devant l'ouverture (9).
PCT/EP1988/000405 1987-08-07 1988-05-09 Appareil d'optique avec dispositif de protection WO1989001643A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
IT3593A/87 1987-08-07
IT8703593A IT1213675B (it) 1987-08-07 1987-08-07 Apparecchio ottico con dispositivodi protezione

Publications (1)

Publication Number Publication Date
WO1989001643A1 true WO1989001643A1 (fr) 1989-02-23

Family

ID=11110321

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP1988/000405 WO1989001643A1 (fr) 1987-08-07 1988-05-09 Appareil d'optique avec dispositif de protection

Country Status (2)

Country Link
IT (1) IT1213675B (fr)
WO (1) WO1989001643A1 (fr)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4991949A (en) * 1990-01-23 1991-02-12 Comar, Inc. Dust protection device for an image sensor
WO2000033119A1 (fr) * 1998-11-27 2000-06-08 Tony Manjah Dispositif de protection et de nettoyage destine a des objets
WO2018211225A1 (fr) * 2017-05-19 2018-11-22 Continental Automotive France Dispositif de vision extérieure pour véhicule, comprenant une caméra
CN109991671A (zh) * 2018-01-03 2019-07-09 福特全球技术公司 车辆物体检测传感器系统

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1243005B (de) * 1966-01-21 1967-06-22 Thomson Houston Comp Francaise Optisches Fenster fuer verunreinigte Umgebungsluft
CH526120A (de) * 1970-08-05 1972-07-31 Licentia Gmbh Anordnung zur Vermeidung des Beschlagens von Okularen

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1243005B (de) * 1966-01-21 1967-06-22 Thomson Houston Comp Francaise Optisches Fenster fuer verunreinigte Umgebungsluft
CH526120A (de) * 1970-08-05 1972-07-31 Licentia Gmbh Anordnung zur Vermeidung des Beschlagens von Okularen

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4991949A (en) * 1990-01-23 1991-02-12 Comar, Inc. Dust protection device for an image sensor
WO2000033119A1 (fr) * 1998-11-27 2000-06-08 Tony Manjah Dispositif de protection et de nettoyage destine a des objets
WO2018211225A1 (fr) * 2017-05-19 2018-11-22 Continental Automotive France Dispositif de vision extérieure pour véhicule, comprenant une caméra
FR3066452A1 (fr) * 2017-05-19 2018-11-23 Continental Automotive France Dispositif de vision exterieure pour vehicule, comprenant une camera
US11220241B2 (en) 2017-05-19 2022-01-11 Continental Automotive France Outside viewing device for a vehicle, comprising a camera
CN109991671A (zh) * 2018-01-03 2019-07-09 福特全球技术公司 车辆物体检测传感器系统

Also Published As

Publication number Publication date
IT1213675B (it) 1989-12-29
IT8703593A0 (it) 1987-08-07

Similar Documents

Publication Publication Date Title
US4899998A (en) Rotational positioning device
US7602485B2 (en) Optical window contamination detecting device for optical apparatus
JPS58108428A (ja) コ−クス温度の測定装置
CA1245187A (fr) Methode et dispositif de detection d'elements en forme de feuilles
EP0289621A1 (fr) Detecteur infrarouge passif de cambriolage pourvu d'un mecanisme de surveillance d'interruptions du champ visuel
CA1326770C (fr) Appareil de mesure de la brillance
WO1989001643A1 (fr) Appareil d'optique avec dispositif de protection
JPH08505101A (ja) 窓ガラス、特に自動車のフロントガラスの湿り度及び／又は汚染度を検出するためのセンサ装置
US5969373A (en) System for detecting small holes in moving articles
KR20060021419A (ko) 검출기구
JPS5884387A (ja) 火災検知装置
US5166536A (en) Method and apparatus for detecting edge cracks
US5963343A (en) Scanner
EP1594099B1 (fr) Ensemble détecteur de sécurité
EP0436354B1 (fr) Outil à main pour déterminer un signal dans une fibre optique par flexion
US6552354B2 (en) Photo device for monitoring setting width of saw teeth
JP4569814B2 (ja) 汚れ検出装置及び監視カメラ並びに汚れ検出方法
US4652125A (en) Film inspection system
US5260583A (en) Method and apparatus for detecting edge cracks
EP1300671B1 (fr) Amélioration des performances d'appareils de mesure de transmission optique
KR101913173B1 (ko) 태양전지패널 표면 오염측정장치
US4687943A (en) Optical motion picture film inspection system
CN114070991A (zh) 一种过鱼监测装置
CN113557106B (zh) 测量设备和方法
US4652124A (en) Film inspection system

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): JP US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE FR GB IT LU NL SE