WO2012160487A2

WO2012160487A2 - Light source device and imaging system including the light source device

Info

Publication number: WO2012160487A2
Application number: PCT/IB2012/052470
Authority: WO
Inventors: Gao Qin LI; Xiao Hui PENG
Original assignee: Koninklijke Philips Electronics N.V.
Priority date: 2011-05-23
Filing date: 2012-05-16
Publication date: 2012-11-29
Also published as: WO2012160487A3; CN102798088A

Abstract

The present invention provides a light source device including a light source base module, the light source base module having a primary surface and a central axis substantially perpendicular to the primary surface and located substantially at the geometric center of the primary surface, wherein the light source base module has one or more light emitting units fitted therein. The light source device also includes a light source adjusting module that can move back and forth along the direction of the central axis. When the light source adjusting module moves back and forth along the direction of the central axis, it can cause swinging of the one or more light emitting units with respect to the central axis, thereby adjusting the illumination angle and/or illumination range of the one or more light emitting units. The present invention also provides an imaging system including a drive device and the above mentioned light source device.

Description

LIGHT SOURCE DEVICE AND IMAGING SYSTEM INCLUDING

THE LIGHT SOURCE DEVICE

FIELD OF THE INVENTION

The present invention relates to the technical field of illumination light sources, and relates in particular to a light source device with an adjustable illumination angle and/or illumination range. The present invention also relates to an imaging system comprising said light source device.

BACKGROUND OF THE INVENTION

A digital imaging system with a charge coupled device (CCD) and a complementary metal oxide semiconductor (CMOS) element as core elements is used widely in people's production and life, especially in the fields of safety protection and health care. Because of restrictions due to principal characteristics, the quality o f an image formed by a CCD and CMOS greatly depends on the illumination of the object and/or person (hereafter collectively called target) to be imaged and the reflection status thereof. Most of the existing imaging products are configured to use a light source to actively provide illumination, so that they can be used independently of environmental conditions. In the case of, for example, a security camera and, for example, a colposcopy, light sources mostly employ LED groups distributed annularly to achieve white light illumination or infrared night vision illumination. The luminance of LEDs of some light sources can be adjusted by controlling the current, which is more convenient to use. However, the illumination angle and/or illumination range of existing imaging products are generally fixed. Furthermore, since CCD, CMOS imaging systems cannot employ internal, coaxial, parallel light illumination, the fixed illumination angle and/or illumination range is not able to self - adapt to optimal illumination conditions for imaging of different imaging targets, different imaging distances and/or different magnification factors; therefore this does not help a user to obtain an optimal image quality. Pure light source products generally employ special lens elements that can move along an axial direction to enable the illumination angle and/or illumination range to be adjusted. However, the superposition of the illumination optical path and the imaging optical path of the light source products often influences important parameters (such as focal length) of imaging systems, so that the image quality will be changed and new problems will occur.

Chinese patent publication, CN 101368708A, published on February 18^th, 2009, titled "An adjusting device for spotlight used in multi-light source operating lamp" discloses an adjusting device for spotlight used in a multi-light source operating lamp, including a lifter used for joining several light source assemblies and a rotating part used for contacting said lifter. The rotation of the rotating part can cause the lifter to go up and down in order to bring one side of the several light source assemblies into motion and then change the illumination angle of the light sources so as to realize the purpose of adjusting the spotlight used, in operation, in a shadowless lamp. But the structure of such an adjusting device for spotlight is complex and clumsy. Besides, the adjusting range of the illumination angle is limited and therefore the adjusting device is inconvenient to use.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a light source device with an adjustable illumination angle and/or illumination range, which can improve the illumination condition of an irradiated target.

In order to attain the above mentioned object, the present invention provides a light source device comprising a light source base module, the light source base module having a primary surface and a central axis substantially perpendicular to the primary surface and located substantially at a geometric center of the primary surface, wherein the light source base module has light emitting unit(s) fitted therein. The light source device also comprises a light source adjusting module that can move back and forth along a direction of the central axis . When the light source adjusting module moves back and forth along the direction of the central axis, it can cause the light emitting unit(s) to swing with respect to the central axis, thereby adjusting the illumination angle and/or illumination range of the light emitting unit(s) .

The technical effects of the light source device are as follows: since the light source device of the present invention includes a light source adjusting module that can move back and forth along the direction of the central axis, the back and forth movement of the light source adjusting module along the direction of the central axis can cause the light emitting unit(s) to swing with respect to the central axis, so that the illumination angle and/or illumination range of the light emitting unit can be easily adjusted.

According to an aspect of the above mentioned light source device of the present invention, the light source base module is provided with at least one through hole in the direction substantially parallel to the central axis to receive the respective light emitting unit(s). The through hole has a pivot protruding from its wall. By means of the pivot, the light emitting unit can be pivotally fitted in the respective through hole. The light source adjusting module is provided with one or more adjusting rods . The orientation of the adjusting rod(s) corresponds to the orientation of the respective through hole(s).

Another aspect of the present invention relates to providing a light source device comprising a light source base module, the light source base module having a primary surface and a central axis substantially perpendicular to the primary surface and substantially located at a geometric center of the primary surface. The light source base module is provided with at least one through hole in a direction substantially parallel to the central axis. The through hole has a pivot protruding from its wall. A light emitting unit is pivotally fitted in the through hole by the pivot. The light source device further comprises a light source adjusting module that can move back and forth along the direction of the central axis. The light source adjusting module is provided with at least one adjusting rod, the orientation of the adjusting rod corresponding to the orientation of the respective through hole, as a result of which, when the light source adjusting module moves back and forth along the direction of the central axis, the light emitting unit is biased by the respective adjusting rod so as to cause the light emitting unit to rotate around the pivot in order to adjust the illumination angle and/or illumination range of the light emitting unit(s).

According to various examples of the above light source device of the present invention:

-the at least one through hole comprises a plurality of through holes distributed on two sides of the central axis or distributed annularly around the central axis to receive a corresponding plurality o f light emitting units. The number and orientation of the adjusting rods correspond to the number and orientation of the through holes, as a result of which the light emitting units can be collectively biased by the respective adjusting rods, so that the light emitting units can collectively swing around the respective pivots in order to adjust the illumination angle and/or illumination range of the light emitting units. The plurality of through holes are distributed uniformly on two sides of the central axis or around the central axis. The pivotal movements of the light emitting units around the respective pivots are synchronous pivotal movements . With respect to the plurality of through holes annularly distributed around the central axis, the pivots of the plurality of light emitting units are respectively arranged tangentially with respect to the annular form;

- the illumination angle can be adjusted between + 90 degrees and -90 degrees, preferably between + 60 degrees and -60 degrees;

- the light emitting unit comprises a fixed seat and an LED embedded into the fixed seat, the rotation of the light emitting unit around the pivot being achieved through a pivotal connection between the fixed seat and the pivot. The fixed seat is provided with a step or bevel on the side facing the adjusting rod to facilitate the adjusting rod to bias the respective light emitting unit;

- the light source adjusting module is provided with a turntable that can rotate independently on the side opposite to the adjusting rods. The rotation of the turntable may cause the light source adjusting module to move back and forth along the direction of the central axis;

-the light source base module further comprises a reset element, one end of which is secured to the through hole 's wall and the other end is connected to the light emitting unit. The reset element is configured to set the light emitting unit at an initial illumination angle when the adjusting rod does not apply bias to the respective light emitting unit and to enable the illumination angle of the light emitting unit to be adjusted when the adjusting rod applies bias to the light emitting unit. The reset element is a spring element or an elastic tether. The light emitting unit is an elongated light emitting unit which has a light exit end and a non - light exit end opposite to the light exit end, the reset element being attached to the light emitting unit near the light exiting end, and the pivot being pivotally connected with the light emitting unit near the non - light exiting end;

-the light emitting unit is pivotally connected to the pivot through a damping element so that the light emitting unit is at an initial illumination angle when the adjusting rod does not apply bias to the light emitting unit and the illumination angle of the light emitting unit is adjustable when the adjusting rod applies bias to the light emitting unit. The damping element is a retaining spring.

Moreover, the present invention provides an imaging system comprising a drive device and the above mentioned light source device. The drive device can automatically control the back and forth movement of the light source adjusting module of the light source device so as to adjust the illumination angle and/or illumination range of the light source device.

According to another aspect of the present invention, the imaging system is a digital imaging system having a CCD or a CMOS automatic zoom imaging part. The drive device can be coupled to the automatic zoom imaging part in order to achieve automatic control of the illumination angle and/or illumination range of the light source device. The imaging part is provided in the proximity of the central axis. The light emitting units surround the imaging part. The imaging system further includes a current adjusting device for the light source, which can adjust the magnitude of the current of the light source to adjust the luminance of the light source. BRIEF DESCRIPTION OF THE DRAWINGS

The specific embodiments of a light source device of the present invention will be exemplarily explained with reference to the attached drawings which illustrate the present invention, without restricting it in any way, in the drawings, in which:

Fig. l is a schematic view showing a structure of the light source device according to the invention when the illumination angle is +a;

Fig.2 is a schematic view showing the structure of the light source device according to the invention when the illumination angle is 0;

Fig.3 is a schematic view showing the structure of the light source device according to the invention when the illumination angle is -b;

Figs.4-6 exemplarily illustrate specific details of the interaction between an adjusting rod and a light emitting unit.

DETAILED DESCRIPTION OF THE INVENTION

Terms and definitions

Illumination Angle: an illumination angle of a light emitting unit 12 is defined as an included angle between a main light exit direction or an average light exit direction 15 and a central axis 3 of a light source base module 1 , such as angles a and b shown in Figs .1 -6.

Referring to Figs.1 -3 , they are schematic views showing a structure of a light source device 100 when the illumination angle of the light source device 100 of the present invention is +a, 0, and -b, respectively. Reference is also made to Figs .4-6, which exemplarily show specific details of the interaction between an adjusting rod 22 and a light emitting unit 12.

Detailed description

The light source device 100 comprises a light source base module 1 and a light source adjusting module 2 which can be displaced in relation to the light source base module 1 . The light source base module 1 includes : a body 1 1 having a primary surface (outer surface) 1 3 ; a central axis 3 substantially perpendicular to the primary surface 13 and located substantially at a geometric center of the primary surface 13 ; and light emitting units 12 installed in the body 1 1 . The light source adjusting module 2 can move back and forth along the direction of the central axis 3 , thereby causing the light emitting units 12 to swing with respect to the central axis 3 in order to enable adjusting an illumination angle and/or an illumination range of the light emitting units 12. The illumination angle can be adjusted between +90 degrees and -90 degrees, preferably between +30 degrees and -30 degrees, most preferably between +60 degrees and -60 degrees.

The light source base module 1 is provided with at least one through hole 10 in a direction substantially parallel to the central axis 3. The through hole 10 has a pivot 14 protruding from its wall. The light emitting unit 12 is pivotally arranged in the respective through hole 10 by means of the pivot 14.

The light source adjusting module 2 includes a body 21 which is provided with adjusting rods 22. The orientation of the adjusting rods 22 corresponds to the orientation of the respective through hole 10, so that, when the light source adjusting module 2 moves back and forth along the direction of the central axis 3 , the light emitting unit(s) 12 can be biased by the respective adjusting rod(s) 22 so as to cause the light emitting unit 12 to rotate around the respective pivot 14 in order to adjust the illumination angle and/or the illumination range of the light emitting unit 12.

In the example shown in Figs.1 -3 , the through holes 3 are a plurality of through holes distributed on two sides of the central axis 3 or distributed annularly around the central axis 3 to receive a corresponding plurality of light emitting units 12. Alternatively, the through hole 10 can be a single through hole 10 situated on one side of the central axis 3 to receive a respective single light emitting unit 12; or the through holes 10 can be 2, 3, 4, 6 or more through holes 10 uniformly or randomly distributed on two sides of the central axis 3 or around the central axis 3. The number and orientation of the adjusting rod(s) 22 correspond to the number and orientation of the through hole(s) 10, thus enabling the light emitting unit(s) 12 to be collectively biased by respective adjusting rod(s) 22, so that the light emitting unit(s) can collectively swing around respective pivot(s) 14 in order to adjust the illumination angle and/or the illumination range of the light emitting unit(s) 12. Preferably, the swings of the light emitting units 12 around respective pivots 14 are synchronous swings. In particular, as to the plurality of through holes 10 distributed annularly around the central axis 3 , the pivots 14 of the plurality of light emitting units 12 are respectively arranged along a tangential direction of the annular form.

Each of the light emitting units 12 comprises a fixed seat (not shown) and an LED embedded into the fixed seat. The rotation of the light emitting unit 12 around the pivot 14 is achieved through a pivotal connection between the fixed seat and the pivot 14. The fixed seat is provided with a step or bevel on the side facing the adjusting rods 22 to facilitate the adjusting rod 22 to bias the respective light emitting unit 12.

The light source adjusting module 2 is provided with a turntable (not shown) that can rotate independently on the side opposite to the adjusting rods 22. The rotation of the turntable may cause the light source adjusting module 2 to move back and forth along the direction of the central axis 3.

The light source base module 1 further comprises reset element(s) 16 , one end of which is secured to the through hole l O's wall and the other end of which is connected to the light emitting unit 12. The reset element 16 is configured to set the light emitting unit 12 at an initial illumination angle when the adjusting rod 22 does not apply bias to the respective light emitting unit 12 and to enable the illumination angle of the light emitting unit to be adjusted when the adjusting rod 22 applies bias to the light emitting unit 12. The reset element 16 can be a spring element or an elastic tether. The light emitting unit 12 is an elongated light emitting unit which has a light exit end and a non - light exit end opposite to the light exit end. The reset element 16 is attached to the light emitting unit 12 near the light exit end. The pivot 14 is pivotally connected with the light emitting unit 12 near the non - light exit end. The light emitting unit 12 can also be pivotally connected to the pivot 14 through a damping element (not shown), so that the light emitting unit 12 is at an initial illumination angle when the adjusting rod 22 does not apply bias to the light emitting unit 12, and the illumination angle of the light emitting unit is adjustable when the adjusting rod 22 applies bias to the light emitting unit 12. The damping element can be e.g. a retaining spring.

The technical effects of the present light source device 100 are as follows: since the light source device 100 of the present invention includes a light source adjusting module 2 that can move back and forth along the direction of the central axis 3 , the back and forth movement of the light source adjusting module 2 along the direction of the central axis 3 can cause the light-emitting units 2 to swing with respect to the central axis 3, so that the illumination angle and/or the illumination range of the light-emitting units 12 can be easily adjusted.

Moreover, the present invention provides an imaging system (not shown) comprising a drive device and the above - mentioned light source device 100. The drive device can automatically control the back and forth movement of the light source adjusting module 2 of the light source device 100 so as to adjust the illumination angle and/or illumination range of the light source device 100.

The imaging system is a digital imaging system containing a CCD or a CMOS automatic zoom imaging part. The drive device can be coupled to the automatic zoom imaging part in order to achieve automatic control of the illumination angle and/or illumination range of the light source device 100. The imaging part is provided in the proximity of the central axis 3. The light emitting units 12 surround the imaging part. The imaging system further includes a current adjusting device for the light source, which can adjust the magnitude of the current of the light source to adjust the luminance of the light source.

It should be understood that although various characteristics and technical effects o f the present invention and specific details of the structure of the present invention are set forth in the above description, they are just exemplary, not limiting. Specific details, especially with respect to shape, size, number and arrangement of the parts of the present invention can be changed without departing from the broad scope and spirit of the principle of the present invention defined by the claims. Singular references do not exclude a plurality. Thus, references to "a", "an" used in claims do not preclude a plurality. The use of such terms is just for the sake of description, and shall not be construed as limiting the scope.

Unless defined otherwise, technical and scientific terms used herein have the same meaning as is commonly understood by one of ordinary skill in the art to which this invention belongs.

It should be understood that the present light source device 100 is not limited to the above described examples. Any variations and equivalents occurring to one of ordinary skill in the art in conjunction with the prior art upon reading the present invention without creative thinking are covered by the claims of the present invention.

Claims

1 . A light source device ( 100) comprising a light source base module ( 1 ), the light source base module having a primary surface ( 13) and a central axis (3) substantially perpendicular to the primary surface and located substantially at a geometric center of the primary surface, characterized in that the light source base module has light emitting unit(s) ( 12) fitted therein, and the light source device also comprises a light source adjusting module (2) that can move back and forth along a direction of the central axis (3), thereby causing the light emitting unit(s) ( 12) to swing with respect to the central axis (3) in order to adjust the illumination angle and/or illumination range of the light emitting unit(s) ( 12).

2. A light source device ( 100) comprising a light source base module ( 1 ), the light source base module having a primary surface ( 13) and a central axis (3) substantially perpendicular to the primary surface and substantially located at a geometric center of the primary surface, characterized in that the light source base module is provided with at least one through hole ( 10) in a direction substantially parallel to the central axis, the through hole having a pivot ( 14) protruding from its wall, and a light emitting unit ( 12) being pivotally fitted in the through hole by the pivot, which light source device further comprises a light source adjusting module (2) that can move back and forth along the direction of the central axis, and which light source adjusting module is provided with at least one adjusting rod (22), the orientation of the adjusting rod corresponding to the orientation of the respective through hole, so that, when the light source adjusting module moves back and forth along the direction of the central axis, the light emitting unit is biased by the respective adjusting rod, causing the light emitting unit to rotate around the pivot in order to adjust the illumination angle and/or the illumination range of the light emitting unit.

3. The light source device according to claim 2, characterized in that: the at least one through hole comprises a plurality of through holes distributed on two sides of the central axis or distributed annularly around the central axis to receive a corresponding plurality o f light emitting units, the number and orientation of adjusting rods corresponding to the number and orientation of the through holes, as a result of which the light emitting units can be collectively biased by the respective adjusting rods, so that the light emitting units can collectively swing around respective pivots in order to adjust the illumination angle and/or the illumination range of the light emitting units.

4. The light source device according to claim 3, characterized in that: the plurality o f through holes are distributed uniformly on two sides of the central axis or around the central axis.

5. The light source device according to claim 3, characterized in that: as to the plurality o f through holes distributed annularly around the central axis, the pivots of the plurality o f light emitting units are respectively arranged tangentially with respect to the annular form.

6. The light source device according to claim 5, characterized in that: the illumination angle can be adjusted between +60 degrees and -60 degrees .

7. The light source device according to claim 2, characterized in that: the light emitting unit comprises a fixed seat and an LED embedded into the fixed seat, the rotation of the light emitting unit around the pivot being achieved through a pivotal connection between the fixed seat and the pivot.

8. The light source device according to claim 7, characterized in that: the fixed seat is provided with a step or bevel on the side facing the adjusting rod to facilitate the adjusting rod to bias the respective light emitting unit.

9. The light source device according to claim 2, characterized in that: the back and forth movement of the light source adjusting module along the direction of the central axis is a sliding movement.

10. The light source device according to claim 2, characterized in that: the light source adjusting module is provided with a turntable that can rotate independently on the side opposite to the adjusting rods, which rotation of the turntable may cause the light source adjusting module to move back and forth along the direction of the central axis.

1 1 . The light source device according to claim 2, characterized in that the light source base module further comprises a reset element ( 16), one end of which is secured to the through hole 's wall and the other end is connected to the light emitting unit, the reset element being configured to set the light emitting unit at an initial illumination angle when the adjusting rod does not apply bias to the respective light emitting unit and to enable the illumination angle of the light emitting unit to be adjusted when the adjusting rod applies bias to the light emitting unit.

12. The light source device according to claim 1 1 , characterized in that: the light emitting unit is an elongated light emitting unit which has a light exit end and a non - light exit end opposite to the light exit end, the reset element being attached to the light emitting unit near the light exit end, and the pivot being pivotally connected with the light emitting unit near the non - light exit end.

13. The light source device according to claim 2, characterized in that: the light emitting unit is pivotally connected to the pivot through a damping element so that the light emitting unit is at an initial illumination angle when the adjusting rod does not apply bias to the light emitting unit and the illumination angle of the light emitting unit is adjustable when the adjusting rod applies bias to the light emitting unit.

14. An imaging system comprising a drive device and the light source device according to any one of claims 1 to 13 , wherein the drive device can automatically control the back and forth movement of the light source adjusting module of the light source device so as to adjust the illumination angle and/or illumination range of the light source device.

15. The imaging system according to claim 14, characterized in that: the imaging system is provided in the proximity of the central axis (3) and comprises a CCD or CMOS automatic zoom digital imaging part, the drive device can be coupled to the automatic zoom imaging part in order to achieve automatic control of the illumination angle and/or illumination range of the light source device.