GB2107897A - Optical automatic critical focusing device - Google Patents
Optical automatic critical focusing device Download PDFInfo
- Publication number
- GB2107897A GB2107897A GB08219994A GB8219994A GB2107897A GB 2107897 A GB2107897 A GB 2107897A GB 08219994 A GB08219994 A GB 08219994A GB 8219994 A GB8219994 A GB 8219994A GB 2107897 A GB2107897 A GB 2107897A
- Authority
- GB
- United Kingdom
- Prior art keywords
- receiver
- transmitter
- mirror
- optics
- optical arrangement
- Prior art date
- Legal status (The legal status 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 status listed.)
- Granted
Links
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B17/00—Systems with reflecting surfaces, with or without refracting elements
- G02B17/08—Catadioptric systems
- G02B17/0896—Catadioptric systems with variable magnification or multiple imaging planes, including multispectral systems
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
- G01S7/481—Constructional features, e.g. arrangements of optical elements
- G01S7/4811—Constructional features, e.g. arrangements of optical elements common to transmitter and receiver
- G01S7/4812—Constructional features, e.g. arrangements of optical elements common to transmitter and receiver transmitted and received beams following a coaxial path
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B17/00—Systems with reflecting surfaces, with or without refracting elements
- G02B17/08—Catadioptric systems
- G02B17/0804—Catadioptric systems using two curved mirrors
- G02B17/0808—Catadioptric systems using two curved mirrors on-axis systems with at least one of the mirrors having a central aperture
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B17/00—Systems with reflecting surfaces, with or without refracting elements
- G02B17/08—Catadioptric systems
- G02B17/0856—Catadioptric systems comprising a refractive element with a reflective surface, the reflection taking place inside the element, e.g. Mangin mirrors
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B17/00—Systems with reflecting surfaces, with or without refracting elements
- G02B17/08—Catadioptric systems
- G02B17/0884—Catadioptric systems having a pupil corrector
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B7/00—Mountings, adjusting means, or light-tight connections, for optical elements
- G02B7/28—Systems for automatic generation of focusing signals
- G02B7/30—Systems for automatic generation of focusing signals using parallactic triangle with a base line
- G02B7/32—Systems for automatic generation of focusing signals using parallactic triangle with a base line using active means, e.g. light emitter
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Engineering & Computer Science (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Computer Networks & Wireless Communication (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Measurement Of Optical Distance (AREA)
- Lenses (AREA)
- Focusing (AREA)
Abstract
An optical automatic critical focusing arrangement for photographic cameras comprises a transmitting diode 1 and a receiver 5. A small concave mirror 2 is provided on the optical axis between the transmitting diode 1 and the receiver 5, which mirror is irradiated by the transmitting diode 1 arranged at its focal point, and additionally has, as a component of the transmitter optics, a rear surface which is provided with a reflecting coating. The small mirror together with a larger concave mirror 3 arranged on the optical axis, forms a mirror lens as the receiver optics. 6a is an optional cover disc or lens. <IMAGE>
Description
SPECIFICATION
Optical automatic critical focussing device
The invention relates to an optical automatic critical focusing arrangement, preferably for photographic cameras which operate with infrared transmitting and receiving units.
In connection with photographic cameras, it is known to use the rays emitted by an infra-red radiator provided on the camera for measuring the distance of the object. The distance is determined from the proportion of the radiation reflected on the object, and according to this distance the automatic critical focusing of the taking lens is effected. The radiation is so focused that it can be directed at specific parts of the image field covered by the camere. The disadvantage of this prior art (DE OS 1 965 064) is the large expenditure of optical components since it is necessary to use two separate systems for the transmitting and receiving units, namely two optically collecting members which are symmetrical about the infra-red radiator. In addition, further reflecting means are necessary for the generation of the partial ray bundles.
It is furthermore known (DE AS 1 953 849) to arrange the infra-red radiator in the focal point of a reflector so that parallel light is emitted. Herein, the transmitter and receiver optics are separately arranged on the optical axis one behind the other.
In the centre of the receiver optics, there is provided an opening for the accommodation of the transmitter optics. In accordance with the focal length of the receiver optics, the whole system is very long in construction. Also, focus setting is only possible by selected zones, that is to say in steps.
Another automatic critics' focusing arrangement (DE AS 2 126 1 18) also necessitates a very large expenditure of optical and opto-electronic components, due to the separate arrangement of the transmitting and receiving units in such a way that there is no cooperative combination of the components.
It is the object of the invention to reduce the expenditure of optical and opto-electronic components for the automatic critical focusing of photographic camera and lenses.
The task underlying the invention is to provide a space-saving combined, preferably infra-red radiation transmitter and receiver unit for automatic critical focusing.
According to the invention, the problem is solved in that a small concave mirror, which is irradiated by a transmitting diode arranged in its focus, additionally has as a component of the transmitter optics a rear surface of wi n a reflecting coating has been applied and which, with a larger concave mirror arranged alignedly in the optical axis, simultaneously forms a mirror lens as the receiver optics. According to a constructional form of the invention, the optically active surfaces of the transmitter and receiver optics components have different spherical or aspherical curvatures. Expediently, the larger concave mirror has in its centre a free opening which is simultaneously designed as a socket for the receiver.It is furthermore proposed according to the invention that there should be provided in front of the transmitting diode a cover disc which may be designed as a lens. This lens in front of the transmitter and receiver optics is advantageously so designed that it has different curvatures for the respective ray path. For the performance of the automatic critical focusing, it is necessary that either the transmitter optics or the concave mirror of the receiver optics is displaceable in the longitudinal direction and can be coupled with the focusing control of the taking lens. The transmitter and receiver optics are therefore preferably arranged in the mount housing of the taking lens or in the camera housing. As the material for the mirror parent substances there may be used glass, ceramics, plastics and/or metal materials.In addition, provision is made for the mirror surfaces to be designed as first surface and/or second surface mirrors.
The invention will be explained in more detail hereinafter. In the accompanying drawings
Figure 1 a shows a lateral view of the transmitter and receiver according to the invention, including the infra-red radiator,
Figures 1 b, c show variants of the lens to be arranged in front of the IR transmitter and receiver,
Figure 2 shows the IR transmitter and receiver with the displaceable concave mirror of the receiver optics,
Figure 3 shows the IR transmitter and receiver optics, with the transmitter optics displaceable.
In known measuring principles of automatic critical focusing, it is necessary to transmit modulated IR rays on the object to be critically focused. For example, in the phase measurement method, an IR transmitting diode is modulated at a specific frequency. The energy is projected on the object via a transmitter optics and the reflected radiation is imaged on the IR receiving diode by a receiver optics. The phase difference between the alternating current energy emitted by the transmitting diode and the energy recollected by the receiving diode serves as a signal for critical focusing. The sharpness external measurement for the automatic critical focusing of optical systems is characterised in that the taking lens is not part of the measuring principle.
Therefore, the proposed optical system is particularly suitable for the phase measurement method because here a fixed optical arrangement that is independent of the object distance is sufficient and only approximate conditions of sharpness have to be observed for the projection on the object as well as the imaging of the radiation reflected by the object. However, if position-sensitive receivers are used for the method, then a coupling of the transmitter or receiver optics with the taking lens is necessary for realising the conditions of sharpness which are required.
As shown in Fig. 1 a, an IR transmitting diode 1 is arranged in the focus of a small concave mirror
2. So as to be aligned in the optical axis, there is
provided behind the small concave mirror 2 a
larger concave mirror 3 with a free opening 4,
through which a light current can be applied to an
IR receiver 5 located therebehind. In front of the
IR transmitting and receiving system, including
the transmitting diode 1, there is arranged a cover
disc 6a, in which there lu located, for example, the
socket of the transmitting diode 1. This cover disc
6a may be constructed as a lens 6b (Fig. 1 b). In
this connection, it is possible for the optical effect
of the lens 6c shown in Fig. 1 c to be different in
the transmitting and receiving zones. By this
means, optimisation of the concave mirrors 2, 3
can be achieved.For example, the mirror
diameters can be kept in smaller dimensions.
The light current emitted by the transmitting
diode 1 is preferably guided to an object as a -parallel light beam. The beam cross-section
bounds the field of measurement. An Image of the
ray proportion reflected by the object is formed on
the IR receiver 5 which is in the "fixed focus"
setting, via the spherical and/or aspherical
surfaces of the concave mirrors 3 and 2, which In
all represent a mirror lens, through the free
opening 4. It is also possible to transmit the light
current from the transmitter at a fixedly set
distance as a convergent beam and to set the
receiver optics to the same distance. The phase
difference between the transmitted and received
signals of the modulated IR radiation, which is
proportional to the object distance, serves as the
criterion of measurement for focusing the taking
lens not shown.
The described optical arrangement may be
accommodated beside the taking lens either
directly in the housing of this lens or in the
camera. As regards the electrical signal
processing, reference is made to the known prior
art.
Fig. 2 shows a variant of the IR transmitter and
receiver according to the invention. Herein, the
concave mirror 3 of the receiver optics is coupled
with the taking lens so as to run in the opposite
direction during its movement, and the
arrangement is thus usable, for example, for the
mentioned method using position-sensitive
receivers. In order to observe specific conditions
of correction, it is possible to use second surface
mirrors having differently curved front and rear
surfaces. The variant shown in Fig. 3 allows a
displacement of the transmitter optical 2,
including the transmittiri 1 diode 1, and during its
movement is coupled with the taking lens so as to
run in the same direction. The application thereof
is also possible in the method given in Fig. 2.
Here, an additional feature is the fact that the free
opening 4 in the concave mirror 3 of the receiver
optics is simultaneously designed as a mounting part and can accommodate the receiver 5.
If the transmitter is fixed, the concave mirror 3 carrying the receiver 5 can again be coupled with the taking lens so as to run in the opposite direction during its movement.
It is within the scope of the invention that the proposed arrangement can be used not only in the infra-red range but also in other ranges of radiation. Over and above this, the twofold utilisation of the optical components, both for transmitting and for receiving, is of great advantage. In addition to a reduction in components, a minimum of space is required for the installation thereof. The arrangement according to the invention furthermore operates irrespective of the type of taking lens used.
Claims (9)
1. An optical automatic critical focusing arrangement comprising a transmitter, a receiver, a small concave mirror, which is irradiated by a transmitting diode arranged at its focal point, additionally has as a component of the transmitter optics a rear surface which is provided with a reflecting coating, said small mirror together with a larger concave mirror being alignedly arranged in the optical axis, forms a mirror lens as the receiver optics.
2. An optical arrangement as claimed in Claim 1, wherein the optically active surfaces of the components of the transmitter and receiver optics have different spherical or aspherical curvatures.
3. An optical arrangement as claimed in Claim 2, wherein the concave mirror has in its centre a free opening which is simultaneously designed as a socket for the receiver.
4. An optical arrangement as claimed in Claim 3, wherein in front of the transmitting diode there is provided a cover disc which may be constructed as a lens.
5. An optical arrangement as claimed in Claim 4, wherein the curvatures of the lens in front of the transmitter and receiver optics are different.
6. An optical arrangement as claimed in Claim 5, wherein the transmitter optics or the concave mirror of the receiver optics is displaceable in the longitudinal direction and can be coupled with the focusing control of the taking lens.
7. An optical arrangement as claimed in Claim 2, wherein the mirror parent substances consist of glass, ceramics, plastics and/or metal materials, and in that the mirror surfaces are designed as first surface and/or second surface mirrors.
8. An optical arrangement as claimed in Claim 7, wherein the transmitter and receiver optics are arranged in the mount housing of the taking lens or in the camera housing.
9. An optical arrangement substantially as described with reference to the accompanying drawings.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DD23412981A DD201245A1 (en) | 1981-10-16 | 1981-10-16 | OPTICAL ARRANGEMENT FOR AUTOMATIC SHARPENING |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB2107897A true GB2107897A (en) | 1983-05-05 |
| GB2107897B GB2107897B (en) | 1985-08-21 |
Family
ID=5534150
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB08219994A Expired GB2107897B (en) | 1981-10-16 | 1982-07-09 | Optical automatic critical focussing device |
Country Status (3)
| Country | Link |
|---|---|
| DD (1) | DD201245A1 (en) |
| DE (1) | DE3227980A1 (en) |
| GB (1) | GB2107897B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2122835A (en) * | 1982-06-30 | 1984-01-18 | Eastman Kodak Co | Rangefinder |
| WO2009070203A1 (en) * | 2007-11-27 | 2009-06-04 | Eastman Kodak Company | Dual focal length lens system |
Families Citing this family (30)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102006031580A1 (en) | 2006-07-03 | 2008-01-17 | Faro Technologies, Inc., Lake Mary | Method and device for the three-dimensional detection of a spatial area |
| DE102009010465B3 (en) | 2009-02-13 | 2010-05-27 | Faro Technologies, Inc., Lake Mary | laser scanner |
| US9551575B2 (en) | 2009-03-25 | 2017-01-24 | Faro Technologies, Inc. | Laser scanner having a multi-color light source and real-time color receiver |
| DE102009015920B4 (en) | 2009-03-25 | 2014-11-20 | Faro Technologies, Inc. | Device for optically scanning and measuring an environment |
| DE102009035336B3 (en) | 2009-07-22 | 2010-11-18 | Faro Technologies, Inc., Lake Mary | Device for optical scanning and measuring of environment, has optical measuring device for collection of ways as ensemble between different centers returning from laser scanner |
| DE102009035337A1 (en) | 2009-07-22 | 2011-01-27 | Faro Technologies, Inc., Lake Mary | Method for optically scanning and measuring an object |
| DE102009055989B4 (en) * | 2009-11-20 | 2017-02-16 | Faro Technologies, Inc. | Device for optically scanning and measuring an environment |
| US9113023B2 (en) | 2009-11-20 | 2015-08-18 | Faro Technologies, Inc. | Three-dimensional scanner with spectroscopic energy detector |
| US9210288B2 (en) | 2009-11-20 | 2015-12-08 | Faro Technologies, Inc. | Three-dimensional scanner with dichroic beam splitters to capture a variety of signals |
| US9529083B2 (en) | 2009-11-20 | 2016-12-27 | Faro Technologies, Inc. | Three-dimensional scanner with enhanced spectroscopic energy detector |
| DE102009057101A1 (en) | 2009-11-20 | 2011-05-26 | Faro Technologies, Inc., Lake Mary | Device for optically scanning and measuring an environment |
| DE102009055988B3 (en) | 2009-11-20 | 2011-03-17 | Faro Technologies, Inc., Lake Mary | Device, particularly laser scanner, for optical scanning and measuring surrounding area, has light transmitter that transmits transmission light ray by rotor mirror |
| US9607239B2 (en) | 2010-01-20 | 2017-03-28 | Faro Technologies, Inc. | Articulated arm coordinate measurement machine having a 2D camera and method of obtaining 3D representations |
| US9628775B2 (en) | 2010-01-20 | 2017-04-18 | Faro Technologies, Inc. | Articulated arm coordinate measurement machine having a 2D camera and method of obtaining 3D representations |
| US9879976B2 (en) | 2010-01-20 | 2018-01-30 | Faro Technologies, Inc. | Articulated arm coordinate measurement machine that uses a 2D camera to determine 3D coordinates of smoothly continuous edge features |
| CN102687433A (en) | 2010-01-20 | 2012-09-19 | 法罗技术股份有限公司 | Portable articulated arm coordinate measuring machine and integrated electronic data processing system |
| DE102010020925B4 (en) | 2010-05-10 | 2014-02-27 | Faro Technologies, Inc. | Method for optically scanning and measuring an environment |
| DE102010032726B3 (en) | 2010-07-26 | 2011-11-24 | Faro Technologies, Inc. | Device for optically scanning and measuring an environment |
| DE102010032725B4 (en) | 2010-07-26 | 2012-04-26 | Faro Technologies, Inc. | Device for optically scanning and measuring an environment |
| DE102010032723B3 (en) | 2010-07-26 | 2011-11-24 | Faro Technologies, Inc. | Device for optically scanning and measuring an environment |
| DE102010033561B3 (en) | 2010-07-29 | 2011-12-15 | Faro Technologies, Inc. | Device for optically scanning and measuring an environment |
| DE102012100609A1 (en) | 2012-01-25 | 2013-07-25 | Faro Technologies, Inc. | Device for optically scanning and measuring an environment |
| DE102012107544B3 (en) | 2012-08-17 | 2013-05-23 | Faro Technologies, Inc. | Optical scanning device i.e. laser scanner, for evaluating environment, has planetary gears driven by motor over vertical motor shaft and rotating measuring head relative to foot, where motor shaft is arranged coaxial to vertical axle |
| DE112013004369T5 (en) | 2012-09-06 | 2015-06-11 | Faro Technologies, Inc. | Laser scanner with additional detection device |
| CN104620129A (en) | 2012-09-14 | 2015-05-13 | 法罗技术股份有限公司 | Laser scanner with dynamical adjustment of angular scan velocity |
| US9513107B2 (en) | 2012-10-05 | 2016-12-06 | Faro Technologies, Inc. | Registration calculation between three-dimensional (3D) scans based on two-dimensional (2D) scan data from a 3D scanner |
| DE102012109481A1 (en) | 2012-10-05 | 2014-04-10 | Faro Technologies, Inc. | Device for optically scanning and measuring an environment |
| US10067231B2 (en) | 2012-10-05 | 2018-09-04 | Faro Technologies, Inc. | Registration calculation of three-dimensional scanner data performed between scans based on measurements by two-dimensional scanner |
| DE102015122844A1 (en) | 2015-12-27 | 2017-06-29 | Faro Technologies, Inc. | 3D measuring device with battery pack |
| CN109814084B (en) * | 2019-03-11 | 2021-02-12 | 上海禾赛科技股份有限公司 | Laser radar system |
-
1981
- 1981-10-16 DD DD23412981A patent/DD201245A1/en unknown
-
1982
- 1982-07-09 GB GB08219994A patent/GB2107897B/en not_active Expired
- 1982-07-27 DE DE19823227980 patent/DE3227980A1/en not_active Withdrawn
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2122835A (en) * | 1982-06-30 | 1984-01-18 | Eastman Kodak Co | Rangefinder |
| WO2009070203A1 (en) * | 2007-11-27 | 2009-06-04 | Eastman Kodak Company | Dual focal length lens system |
| US7573654B2 (en) | 2007-11-27 | 2009-08-11 | Eastman Kodak Company | Dual focal length lens system |
| CN101874218A (en) * | 2007-11-27 | 2010-10-27 | 伊斯曼柯达公司 | Dual focal length lens system |
| CN101874218B (en) * | 2007-11-27 | 2012-09-26 | 伊斯曼柯达公司 | Dual focal length lens system |
Also Published As
| Publication number | Publication date |
|---|---|
| DE3227980A1 (en) | 1983-05-05 |
| GB2107897B (en) | 1985-08-21 |
| DD201245A1 (en) | 1983-07-13 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PCNP | Patent ceased through non-payment of renewal fee |