Patent Publication Number: US-2020296808-A1

Title: Constant Light System and Ambient-Light Intensity Detector Thereof

Description:
CROSS REFERENCE OF RELATED APPLICATION 
     This is a U.S. National Stage under 35 U.S.C. 119(a-d) to Chinese application number 2019101972997, filed Mar. 15, 2019. 
     NOTICE OF COPYRIGHT 
     A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to any reproduction by anyone of the patent disclosure, as it appears in the United States Patent and Trademark Office patent files or records, but otherwise reserves all copyright rights whatsoever. 
     BACKGROUND OF THE PRESENT INVENTION 
     Field of Invention 
     The present invention relates to an ambient-light detecting apparatus, and more particularly to a constant light system and an ambient-light intensity detector thereof. 
     Description of Related Arts 
     Smart light fixture is widely used in recent years. A conventional smart light fixture typically includes a processing system, at least one light sensor and at least one lighting fixture, wherein each light sensor and each lighting fixture are electrically and/or communicatively linked with the processing system. Each light sensor includes a potentiometer adapted for adjustably indicating a detecting value of the light sensor when the smart lamp fixture is utilized in a particular use environment. In particular, the detecting value of the light sensor is associated with an expected ambient-light intensity. For instance, while the intensity of the ambient light is detected lower than the present detecting value of the light sensor, the light sensor would generate a detecting signal which is then received and processed by the processing system in other to control the operation status of the light fixture subsequently, for example, to selectively turn on the light fixture or adjust the luminous intensity of the lighting fixtures, ensuring the intensity of the ambient light of the use environment meeting the users&#39; expectation. Although the conventional smart light fixture provides much convenience, it still has a lot of drawbacks. 
     Firstly, since the light sensor detects the intensity of the ambient light by receiving and analyzing a reflection light from a stationary object in the use environment, the detection result of the light sensor is vulnerably influenced by the reflectivity index of the corresponding reflecting object, causing a detection offset with the actual intensity of the ambient-light. More specifically, there is a diversity of objects in the use environment that, for example, in an office room, the objects would be the desks, A4-paper disposed on the desk, keyboards, screen of a cellphone, and so on, which are made of different materials and in different colors and have different reflectivity indexes at their reflecting surface respectively, such that the detection results of the light sensor corresponding to the different reflection lights from different reflecting surfaces are various or even opposite. In other words, the detection result of the conventional smart light fixture may be interfered by the objects in the use environment. 
     Secondly, the detecting value of the light sensor of the conventional smart light fixture is controllably adjusted by the potentiometer. The core configuration of the potentiometer includes a slid rheostat, which is configured to adjust the detecting value of the light sensor by changing the relative positions between a resistor body and a removable brush thereof, that causes errors in the detecting value of the light sensor. 
     More specifically, even if the current relative position of the resistor body and the removable brush of the potentiometer are adjusted to be consistent with the previous one, the detecting value of the light sensor at the current position is still different from that of the previous one. If the conventional smart light fixture merely includes one light sensor, the error generated by the potentiometer has little impact on the conventional smart light fixture, but when the conventional smart light fixture includes multiple light sensors, the detecting values of multiple light sensors may not be unified to detect an actual intensity of the ambient light due to the error caused by the potentiometer. 
     SUMMARY OF THE PRESENT INVENTION 
     The invention is advantageous in that it provides a constant light system and an ambient-light intensity detector thereof, wherein the adverse effects to the detection accuracy of the ambient-light intensity detector caused by different surface reflectivity indexes of the one or more objects in the use environment can be minimized, so as to improve the accuracy of the detection result of the ambient-light intensity detector. 
     Another advantage of the invention is to provide a constant light system and an ambient-light intensity detector thereof, wherein by virtualizing the reflection light from the corresponding object in the use environment, the ambient-light intensity detector is capable of reducing the adverse effects to the accuracy of the detection results of the ambient-light intensity detector with respect to the different surface reflectance of the one or more objects in the use environment. 
     Another advantage of the invention is to provide a constant light system and an ambient-light intensity detector thereof, wherein the ambient-light intensity detector contains a plurality of preset control scales corresponding to the detecting values of the photosensitive element respectively. 
     Another advantage of the invention is to provide a constant light system and an ambient-light intensity detector thereof, wherein the ambient-light intensity detector provides a plurality of preset control scales so as to facilitate the unifying of the detecting values of the multiple ambient-light intensity detectors. 
     Another advantage of the invention is to provide a constant light system and an ambient-light intensity detector thereof, wherein the detection range of the ambient-light intensity detector can be adjusted according to the actual condition of the use environment, so as to improve the applicability and flexibility thereof. 
     Another advantage of the invention is to provide a constant light system and an ambient-light intensity detector thereof, wherein the ambient-light intensity detector comprises a light-uniforming element and a light-converging element, wherein the light-converging component defines a light-converging path, and the light-uniforming component and the photosensitive surface of the photosensitive element are retained in the light-converging path, wherein the light-uniforming component is configured to make the reflection lights reflected from the one or more objects losing their original propagation directions during passing through the light-uniforming component, wherein the light-converging component is configured to converge the reflected lights of the one or more objects to the light-converging path. 
     Another advantage of the invention is to provide a constant light system and an ambient-light intensity detector thereof, wherein during detecting the intensity of the ambient light in the use environment, the ambient-light intensity detector enables the reflection lights losing their original propagation directions while passing through the light-uniforming component to form one or more pending detection lights which are then converged to the light-converging path by the light-converging component for being received and sensed at the photosensitive surface of the photosensitive element, such that the adverse effects to the accuracy of the detection results of the ambient-light intensity detector with respect to the different surface reflectance of the one or more objects in the use environment can be substantially reduced. 
     Another advantage of the invention is to provide a constant light system and an ambient-light intensity detector thereof, wherein a distance between the light-converging component and the photosensitive element can be adjusted so as to adjust a detection range of the ambient-light intensity detector, such that the ambient-light intensity detector is adapted to be applied in many different applications in various use environments. 
     Another advantage of the invention is to provide a constant light system and an ambient-light intensity detector thereof, wherein the light-converging component defines a central axis, wherein the light-converging component is configured to converge non-selectively and undistinguishably the pending detection lights around the central axis to the light-converging component. 
     Another advantage of the invention is to provide a constant light system and an ambient-light intensity detector thereof, wherein the light-uniforming component is configured to uniformly and evenly mix the reflection lights around the central axis nonselectively to form the pending detection lights. 
     Another advantage of the invention is to provide a constant light system and an ambient-light intensity detector thereof, wherein the photosensitive is configured to arrange the photosensitive surface of the photosensitive element perpendicular to the central axis of the light-converging component, such that the pending detection lights, after being converged to the light-converging path by the light-converging component, can be directly received at the photosensitive surface of the photosensitive element. 
     Another advantage of the invention is to provide a constant light system and an ambient-light intensity detector thereof, wherein the ambient-light intensity detector further comprises a light-deflecting element, configured to change the propagation directions of the pending detection lights, enabling the pending detection lights to be received and sensed by the photosensitive surface of the photosensitive element. 
     Another advantage of the invention is to provide a constant light system and an ambient-light intensity detector thereof, wherein the ambient-light intensity detector comprises a housing which defines a detection environment, wherein the photosensitive element receives the pending detection light in the detection environment to detect the intensity of the ambient light of the use environment, so as to avoid the interference of the detection result of the ambient-light intensity detector by the direct external light. 
     Another advantage of the invention is to provide a constant light system and an ambient-light intensity detector thereof, wherein the ambient-light intensity detector comprises a controller electrically and/or communicatively linked with the photosensitive element, wherein the controller contains a plurality of preset control scales corresponding to the detecting values respectively. In other words, the ambient-light intensity detector provides the plurality of preset control scales to unify the detecting values in various use environments. 
     Additional advantages and features of the invention will become apparent from the description which follows, and may be realized by means of the instrumentalities and combinations particular point out in the appended claims. 
     According to the present invention, the foregoing and other objects and advantages are attained by an ambient-light intensity detector, comprising: 
     a light-uniforming component configured to uniformly and evenly mix reflection lights reflected from one or more objects to form pending detection lights during the reflection light passing through the light-uniforming component; 
     a light-converging component defining a light-converging path, wherein the light-uniforming component is retained in the light-converging path, and the light-converging component is configured to converge the pending detection lights to the light-converging path; and 
     a photosensitive element having a photosensitive surface, wherein the photosensitive surface of the photosensitive element is retained in the light-converging path and configured to receive the pending detection lights after being converged to the light-converging path by the light-converging component. 
     According to the present invention, the foregoing and other objects and advantages are attained by a constant light system which comprises: 
     a control system which comprises a plurality of preset control scales; 
     one or more lighting fixtures which are controllably linked with the control system; and 
     an ambient-light intensity detector, which comprises: 
     a light-uniforming component configured to uniformly and evenly mix reflection lights reflected from one or more objects to form pending detection lights during the reflection light passing through the light-uniforming component; 
     a light-converging component defining a light-converging path, wherein the light-uniforming component is retained in the light-converging path, and the light-converging component is configured to converge the pending detection lights to the light-converging path; and 
     a photosensitive element having a photosensitive surface, wherein the photosensitive surface of the photosensitive element is retained in the light-converging path and configured to receive and detect the pending detection lights after being converged to the light-converging path through the light-converging component, wherein the photosensitive element is communicatively linked with the control system in such a manner that when the intensity of the pending detection lights varies, the control system is capable of controlling the ambient-light intensity of the one or more lighting fixtures according to the plurality of preset control scales, so as to ensure the illuminance of the detection area corresponding to the configured preset control scales to be retained in a constant value. 
     According to the present invention, the foregoing and other objects and advantages are attained by a manufacturing method of an ambient-light intensity detector, comprising the following steps. 
     (a) Provide a light-uniforming component and a light-converging component in a receiving cavity of a housing. 
     (b) Install a circuit board with a photosensitive element attached thereto in the receiving cavity of the housing at an upper end portion thereof, wherein a photosensitive surface of the photosensitive element is retained in a light-converging path defined by the light-converging component to form the ambient-light intensity detector. 
     According to the present invention, the foregoing and other objects and advantages are attained by a detecting method of an ambient light intensity, comprising the following steps. 
     (A) Make a reflection light reflected from an object in a use environment losing its original propagation direction to form a pending detection light. 
     (B) Converge the pending detection light to a light-converging path; and 
     (C) Receive, at a photosensitive surface of a photosensitive element which is retained in the light-converging path, the detection light, so as to detect the intensity of the ambient-light of the use environment. 
     Still further objects and advantages will become apparent from a consideration of the ensuing description and drawings. 
     These and other objectives, features, and advantages of the present invention will become apparent from the following detailed description, the accompanying drawings, and the appended claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an ambient-light intensity detector according to a first preferred embodiment of the present invention. 
         FIG. 2  is an exploded view of the ambient-light intensity detector according to the first preferred embodiment of the present invention. 
         FIG. 3A  is a partial sectional front perspective view of the ambient-light intensity detector according to the above first preferred embodiment of the present invention. 
         FIG. 3B  is a partial sectional rear perspective view of the ambient-light intensity detector according to the above first preferred embodiment of the present invention. 
         FIG. 4  is a sectional view of the ambient-light intensity detector according to the above first preferred embodiment of the present invention, illustrating the detecting of the light intensity of a use environment. 
         FIG. 5A  is a sectional view of the ambient-light intensity detector according to a first alternative mode of the above first preferred embodiment of the present invention. 
         FIG. 5B  is a sectional view of the ambient-light intensity detector according to a second alternative mode of the above first preferred embodiment of the present invention. 
         FIG. 5C  is a sectional view of the ambient-light intensity detector according to a third alternative mode of the above first preferred embodiment of the present invention. 
         FIG. 5D  is a sectional view of the ambient-light intensity detector according to a fourth alternative embodiment of the first preferred embodiment of the present invention. 
         FIG. 6  is a perspective view of the ambient-light intensity detector according to a fifth alternative mode of the above first preferred embodiment of the present invention. 
         FIG. 7A  is a schematic view of a constant light system according to a preferred embodiment of the present invention. 
         FIG. 7B  is a schematic view of the constant light system according to an alternative mode of the above preferred embodiment of the present invention. 
         FIG. 8A  is a partial sectional front perspective view of an ambient-light intensity detector according to a second preferred embodiment of the present invention. 
         FIG. 8B  is a partial sectional rear perspective view of the ambient-light intensity detector according to the above second preferred embodiment of the present invention. 
         FIG. 8C  is a sectional view of the ambient-light intensity detector according to the above second preferred embodiment of the present invention, illustrating the detecting of the light intensity of ambient light of the use environment. 
         FIG. 9A  is a partial sectional front perspective view of an ambient-light intensity detector according to a third preferred embodiment of the present invention. 
         FIG. 9B  is a partial sectional rear perspective view of the ambient-light intensity detector according to the above third preferred embodiment of the present invention. 
         FIG. 9C  is a sectional view of the ambient-light intensity detector according to the above third preferred embodiment of the present invention, illustrating the detecting of the light intensity of ambient light of the use environment. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The following description is disclosed to enable any person skilled in the art to make and use the present invention. Preferred embodiments are provided in the following description only as examples and modifications will be apparent to those skilled in the art. The general principles defined in the following description would be applied to other embodiments, alternatives, modifications, equivalents, and applications without departing from the spirit and scope of the present invention. 
     Referring to the  FIG. 1  to  FIG. 4  of the drawings, an ambient-light intensity detector according to a first preferred embodiment of the present invention is illustrated, wherein the ambient-light intensity detector  100  comprises a light-uniforming component  10 , a light-converging component  20  and a photosensitive element  30 , wherein the light-converging component  20  defines a light-converging path  40 . The light-uniforming component  10  is retained in the light-converging path  40  defined by the light-converging component  20  and configured to uniformly and evenly mix the reflection lights reflected from one or more objects in a use environment (where the detector  100  is utilized) to form one or more pending detection lights during the reflection light passing through the light-uniforming component  10 . The light-converging component  20  is configured to converge the detection lights to the light-converging path  40 . The photosensitive element  30  has a photosensitive surface  31  retained in the light-converging path  40  defined by the light-converging component  20  and configured to be able to receive the pending detection lights converged in the light-converging path  40  by the light-converging component  20  for processing a detection of the pending detection lights by the photosensitive element  30  so as to detect the intensity of the ambient light in the use environment. 
     Accordingly, the ambient-light intensity detector  100  is configured to process a light uniforming treatment by means of the light-iniforming component  10  to uniformly and evenly mix the one or more reflection lights reflected from one or more objects in the use environment (for example, as shown in  FIGS. 4, 7A, 7B, 8C, 9C , the reflection lights illustrated as dotted lines entering the light-uniforming component  10  being reflected by one or more objects in the use environment (not shown in figures) transmitting through the light-uniforming component  10 ), wherein the light-uniforming component  10  is configured to make the one or more reflection lights losing their original propagation directions to form the uniform and even pending detection lights, i.e. to virtualize the one or more reflection lights of the one or more objects, so that the adverse effects to the accuracy of the detection result of the ambient-light intensity detector  100  with respect to the different surface reflectance of the one or more objects in the use environment can be reduced. In other words, the ambient-light intensity detector  100  is able to weaken or even eliminate the adverse effects to the detection accuracy of the ambient-light intensity detector  100  caused by the different surface reflectance of the one or more objects in the use environment by uniformly and evenly mix the one or more reflection lights from the one or more objects in the use environment through the light-uniforming component  10  according to the present invention, such that the detection result obtained by the ambient-light intensity detector  100  is capable of matching with the actual condition of the use environment. 
     Accordingly, the ambient-light intensity detector  100  is able to increase its detection range by converging and/or gathering as much as pending reflection lights to the light-converging path  40  by means of the light-converging component  20 , such that the adverse effects to the detection accuracy caused by the different surface reflectance of the one or more objects in the use environment can be further reduced. 
     Please referring to  FIGS. 1 to 4  of the drawings, the light-converging component  20  of the ambient-light intensity detector  100  is embodied as a light transmissive optical element that is configured to refract the pending detection lights while passing through the light-converging component  20  and converge the pending detection lights to the light-converging path  40 . Accordingly, the light-converging component  20  has an light-entering side  21  and an opposing light-emerging side  22  corresponding to the light-entering side  21 , wherein the light-uniforming component  10  is retained in the light-converging path  40  adjacent to the light-entering side  21  of the light-converging component  20  and the photosensitive element  30  is retained in the light-converging path  40  adjacent to the light-emerging side  22  of the light-converging component  20 , such that the one or more reflection lights reflected from the one or more objects in the use environment being uniformly and evenly mixed to form the pending detection lights after passing through the light-uniforming component  10  are ensured to be refracted and converged to the light-converging path  40  for being received at the photosensitive surface  31  of the photosensitive element  30 . 
     Preferably, the light-converging component  20  is embodied as a Fresnel lens to reduce the size of the light-converging component  20  and the manufacturing cost of the ambient-light intensity detector  100 . In particular, the light-converging component  20  has a light-entering surface  23  and an opposing light-emerging surface  24 , wherein the light-entering surface  23  of the light-converging component  20  is a side surface of the light-entering side  21  of the light-converging component  20  and has a plurality of concentric circular protruding tooth. Correspondingly, the light-emerging surface  24  of the light-converging component  20  is a flat light emerging surface formed at a side surface of the light-emerging side  22  of the light-converging component  20 . Accordingly, the pending detection lights enter the light-converging component  20  from the light-entering surface  23  of the light-converging component  20  and emerge from the light-emerging surface  24  of the light-converging component  20 , wherein the pending detection lights are converged to the light-converging path  40  through the light-converging component  20  and then the converged detection lights is received by the photosensitive element  30  at its photosensitive surface  31 . 
     Furthermore, the light-converging component  20  defines a central axis  201 , as shown in  FIG. 3B , wherein the cross section of the light-converging component  20  has a centrosymmetric circular cross section along the thickness of the light-converging component  20  while the symmetric center of the light-converging component  20  is the central axis  201  of the light-converging component  20 , such that the pending detection lights uniformly and evenly mixed from the reflection lights around the ambient-light intensity detector  100  by the light-uniforming component  10  can all be refracted and converged to the light converge path  40  by means of the light-converging component  20  nonselectively, such that the detection accuracy of the ambient-light intensity detector  100  can be enhanced. 
     As shown in the  FIGS. 1 to 4  of the drawings, the light-uniforming component  10  has a light-inletting side  11  and an opposing light-outletting side  12  correspondingly, wherein the light-uniforming component  10  is retained in the light-converging path  40  defined by the light-converging component  20  that the light-outletting side  12  of the light-uniforming component  10  faces towards the light-entering side  21  of the light-converging component  20 , such that the one or more reflection lights from the one or more objects in the use environment firstly enters the light-uniforming component  10  from its light-inletting side  11  and then emerges from its light-outletting side  12 , wherein the reflection lights are uniformly and evenly mixed and/or diffused by the light-uniforming component  10  to form the uniform and even pending detection lights adapted to be detected by the photosensitive element  40  in the ambient-light intensity detector  100 . The pending detection light enters the light-converging component  20  from its light-entering side  21  and gets out from its light-emerging side  22 , wherein the pending detection light is refracted and converged to the light-converging path  40  through the light-converging component  20 . 
     Preferably, the light-uniforming component  10  has a centrosymmetric cross section along the thickness of the light-uniforming component  10  and the symmetric center of the light-uniforming component  10  is positioned along the central axis  201  defined by the light-converging component  20 , such that the reflection lights around the ambient-light intensity detector  100  can be nonselectively mixed and/or diffused by the light-uniforming component  10  uniformly and evenly to form the uniform pending detection lights. 
     In other words, according to the ambient-light intensity detector  100  of the preferred embodiment as illustrated in the  FIGS. 1-4 , the central axis  201  extends through the centers of the light-uniforming component  10  and the light-converging component  20 , and that the cross sections of the light-converging component  20  and the light-uniforming component  10  at any position along their thickness directions are centrosymmetric shapes, and the symmetric centers of which are located along the central axis  201  defined by the light-converging component. 
     Furthermore, the light-uniforming component  10  has a light-inletting surface  13  and an opposing light-outletting surface correspondlgy, wherein the light-inletting surface  13  is a side surface of the light-inletting side  11  of the light-uniforming component  10  and the light-outletting surface  14  is a side surface of the light-outletting side  12  of the light-uniforming component  10 . Accordingly, the one or more reflection lights reflected from the one or more objects in the use environment enter the light-uniforming component  10  from its light-inletting surface  13  and emerge from its light-outletting surface  14  so as to form the uniform pending detection lights. 
     It is worth mentioning that the types of the light-inletting surface  13  and the light-outletting surface  14  of the light-uniforming component  10  are not intended to be limited according to the preferred embodiment of the present invention. For instance, both of the light-inletting surface  13  and the light-outletting surface  14  of the light-uniforming component  10  can be embodied as smooth surfaces or both rough surfaces. Alternatively, the light-inletting surface  13  and the light-outletting surface  14  can be different types that, for example, one is a smooth surface and the other is a rough surface. 
     It is worth mentioning that although the light-inletting surface  13  and the light-outletting surface  14  of the light-uniforming component  10  are embodied as flat surfaces as an example as shown in the  FIG. 1  to  FIG. 4  of the drawings according to the present invention, person skilled in the art would understand that the description and features of the ambient-light intensity detector  100  in this embodiment, as shown in the  FIG. 1  to  FIG. 4 , are not intended to limit the scope of the ambient-light intensity detector  100  of the present invention. In some examples, both the light-inletting surface  13  and the light-outletting surface  14  of the light-uniforming component  10  can be embodied as arc surfaces such as convex arc surface and concave arc surface. Alternatively, one of the light-inletting surface  13  and the light-outletting surface  14  of the light-uniforming component  10  is embodied as a convex arc surface and the other is embodied as a concave arc surface. 
     Referring to  FIG. 1  to  FIG. 4 , a gap  101  is formed between the light-outletting surface  14  of the light-uniforming component  10  and the light-entering surface  23  of the light-converging component  20 . In other words, the ambient-light intensity detector  100  further has a gap  101  defined between the light-outletting surface  14  of the light-uniforming component  10  and the light-entering surface  23  of the light-converging component  20 . Accordingly, the one or more pending detection lights, emerging from the light-outletting surface  14  of the light-uniforming component  10 , propagate through the gap  101  and enter the light-converging component  20  from the light-entering surface  23  of the light-converging component  20 , wherein gas, such as, but not limited to, air, is filled in the gap  101  for reducing energy-loss of the pending detection lights while being converged to the light-converging path  40  by the light-converging component  20 , so as to further enhance the detection accuracy of the ambient-light intensity detector  100 . 
     Optionally, in an alternative mode of the light-uniforming component  10  of the preferred embodiment, the light-outletting surface  14  of the light-uniforming component  10  are overlappedly attached to the light-entering surface  23  of the light-converging component  20  as illustrated, such that the one or more pending detection lights, emerging from the light-outletting surface  14  of the light-uniforming component  10 , directly enter the light-converging component  20  from its light-entering surface  23 . 
     In addition, referring to  FIGS. 1-4 , in this preferred embodiment of the ambient-light intensity detector  100  of the present invention, the ambient-light intensity detector  100  further comprises an enclosing  50  comprising a tubular housing  51 , wherein the housing  51  has an upper end  511 , an opposing lower end  512  and a receiving cavity  513  extended from the lower end  512  to the upper end  511 . As shown in the  FIGS. 1 to 4  of the drawings, the light-uniforming component  10 , the light-converging component  20  and the photosensitive element  30  are installed to retain within the receiving cavity  513  of the housing  51  along a longitudinal direction of the housing  51  to define a detection environment  102  within the tubular housing  51  in order to avoid any interference of the external light to the detection result of the ambient-light intensity detector  100 . 
     More specifically, the light-uniforming component  10  is retained in the receiving cavity  513  of the housing  51  by mounting and supporting the sidewall of the light-uniforming component  10  with the inner wall of the housing  51  while the light-inletting surface  13  of the light-uniforming component  10  facing the outside of the housing  51 . The light-converging component  20  is retained in the receiving cavity  513  of the housing  51  by mounting and supporting the sidewall of the light-converging component  20  by the inner wall of the housing  51 . The photosensitive element  30  is suspendedly retained in the receiving cavity  513  of the housing  51  with its photosensitive surface  31  facing to the light-emerging surface  24  of the light-converging component  20 , wherein a central axis  201  of the light-converging component  20  extended through a center of the photosensitive surface  31  of the photosensitive element  30 . When the ambient-light intensity detector  100  is detecting the intensity of the ambient light, external light is blocked from entering the receiving cavity  513  of the housing  51  by the surrounding wall of the housing  51 , wherein ambient light can only enters into the receiving cavity  513  of the housing  51  through the light-inletting side  11  of the light-uniforming component  10 , such that the photosensitive surface  31  of the photosensitive element  30  is only allowed to receive and detect the one or more pending detection lights converged to the light-converging path  40  by the light-converging component  20 , so as to avoid the interference of the external light to the detection accuracy of the ambient-light intensity detector  100 . 
     According to this preferred embodiment of the present invention, referring to  FIGS. 1-4 , the ambient-light intensity detector  100  further comprises a circuit board  60  mounted and retained in the receiving cavity  513  of the housing  51  in a suspending manner, wherein the photosensitive element  30  is mounted to the circuit board  60  so as to be suspendedly retained in the receiving cavity  513  of the housing  51 . 
     Preferably, the circuit board  60  is extended in a direction consistent with the longitudinal direction of the housing  51 , that is the circuit board  60  is extended along the longitudinal direction of the housing  51  while the plane defined by the photosensitive surface  31  of the photosensitive element  30  is perpendicular to the extending direction of the circuit board  60 . In other words, the photosensitive surface  31  of the photosensitive element  30  is perpendicular to the circuit board  60 , such that the photosensitive surface  31  of the photosensitive element  30  is able to face towards the light-emerging surface  24  of the light-converging component  20 . Alternatively, the extending direction of the circuit board  60  is perpendicular to the longitudinal direction of the housing  51  and the photosensitive element  30  is attached on the circuit board  60  in such a manner that the plane defined by the photosensitive surface  31  of the photosensitive element  30  is parallel to the extending direction of the circuit board  60 , such that the photosensitive surface  31  of the photosensitive element  30  and the light-emerging surface  24  of the light-converging component  20  are parallel in face to face manner. 
     The housing  51  further comprises a cover  52  having a through hole  521 , wherein the receiving cavity  513  of the housing  51  is thoroughly extended from the lower end  512  to the upper end  511  of the housing  51 , wherein after the circuit board  60  is installed in the receiving cavity  513  of the housing  51 , the cover  52  is mounted in the receiving cavity  513  of the housing  51  to cover and enclose an upper opening at the upper end  511  of the receiving cavity  513  of the housing  51  and an electric wiring is fittingly passed through the through hole  521  of the cover  52  and extended into the receiving cavity  513  of the housing  51  to electrically link the circuit board  60  with a power source, an electrical terminal or a predetermined apparatus that the detection result of the ambient-light intensity detector  100  is required. 
     Furthermore, the housing  51  has at least two opposing engaging slots  514  formed in the surrounding wall of the housing  51  at the upper end  511  thereof and communicating with the receiving cavity  513  with outside. The cover  52  further comprises a cover body  522 , at least two opposing mounting arms  523  extended from the cover body  522 , and at least two engaging protrusions  524  protruded from free ends of the mounting arms  523  respectively. The cover  52  is installed at the upper end  511  of the housing  51  by inserting the cover  52  into the upper opening of the receiving cavity  513  of the housing  51  and engaging the two engaging protrusions  524  of the mounting arms  523  of the cover  52  into the two engaging slots  514  of the housing  51  respectively and automatically due to the elasticity of the mounting arms  523 , so as to enclose the upper opening of the receiving cavity  513  of the housing by the cover  52 . 
     As shown in the  FIGS. 1 to 4  of the drawings, the enclosure  50  further comprises a first installing ring  53  and a second installing ring  54 , wherein threads are formed at the inner walls of the first installing ring  53  and the second installing ring  54 . Accordingly, the housing  51  has a thread portion provided at the outer surrounding wall thereof, wherein the first installing ring  53  is mounted on the housing  51  by engaging the threads at the inner wall thereof with the thread portion at the outer surrounding wall of the housing  51 . Similarly, the second installing ring  54  is mounted at the housing  51  by engaging the threads of the inner wall thereof with the thread portion at the outer surrounding wall of the housing  51  too. Therefore, the first installing ring  53  and the second installing ring  54  can incorporated with each other for installing the ambient-light intensity detector  100  to a stationary fixture. 
     For example, the stationary fixture can be a ceiling which has an installing hole, wherein the diameter of the outer surrounding wall of the housing  51  is no less than the diameter of the stationary fixture, wherein the diameters of the outer walls of the first installing ring  53  and second installing ring  54  are larger than the diameter of the stationary fixture. During mounting the ambient-light intensity detector  100  to the stationary fixture, the second installing ring  54  is firstly mounted on the housing  51 , then the upper end  511  of the housing  51  is aligned with and passes through the installing hole of the stationary fixture, and then the first installing ring  53  is mounted on the housing  51  thirdly. As such, the ambient-light intensity detector  100  is installed to the stationary fixture in a manner that the stationary fixture is sandwichedly supported by the first installing ring  53  and second installing ring  54  mounted at two sides of the stationary fixture. 
     Alternatively, the first installing ring  53  can be integrally formed on the housing  51 , while the second installing ring  54  is mounted on the housing  51  via a threaded joint means, or that the first installing ring  53  is mounted on the housing  51  via the threaded joint means while the second installing ring  54  is integrally formed on the housing  51 , according to an alternative mode of the preferred embodiment of the present invention. 
     In addition, referring to  FIGS. 1-4 , according to the preferred embodiment of the present invention, the ambient-light intensity detector  100  further comprises a controller  70 , wherein the photosensitive element  30  is controllably connected to the controller  70 , wherein the controller  70  has a plurality of preset control scales for controlling the detecting values of the photosensitive element  30 . In other words, the plurality of preset control scales of the controller  70  are corresponding to the detecting values of the photosensitive element  30  respectively, that is the preset control scales of the controller  70  have a one-to-one mapping relationship with the detecting values of the photosensitive element  30 . 
     According to the preferred embodiment of the present invention, by configuring the plurality of preset control scales, the ambient-light intensity detector  100  is enabled to maintain the consistence of the detecting values of the photosensitive element  30  when the controller  70  is adjusted to the same preset control scale in different time periods, thereby enhancing the controllability of the ambient-light intensity detector  100 . For example, the preset control scales of the controller  70  comprises “0-control scale”, “1-control scale”, “2-control scale”, “3-control scale”, “4-control scale”, “5-control scale”, “6-control scale”, “7-control scale”, “8-control scale”, “9-control scale”, “A-control scale”, “B-control scale”, “C-control scale”, “D-control scale”, “E-control scale”, and “F-control scale”, wherein when the controller  70  is adjusted from the “A-control scale” to any other control scale and then returned back to the “A-control scale”, the detecting value of the photosensitive element  30  remains the same while being at the “A-control scale” twice, such that the controllability of the ambient-light intensity detector  100  is enhanced. 
     Accordingly, according to the preferred embodiment of the present invention, by configuring the plurality of preset control scales by the controller  70 , the ambient-light intensity detector  100  is able to maintain the consistence of the detecting values of the photosensitive element  30 , so as to enhance the controllability of the ambient-light intensity detector  100 . For instance, when two ambient-light intensity detectors  100  are utilized in the use environment, after the controllers  70  of the two ambient-light intensity detectors  100  are both adjusted to the “A-control scales”, the detecting values of the two photosensitive elements  30  are set to be equal with each other, so that the controllability of the ambient-light intensity detectors  100  are enhanced. 
     Preferably, the controller  70  is embodied as a coding switch, such as a BDC coding switch, adapted to selectively switch among the plurality of preset control scales for adjusting the controller  70 . For example, the controller  70  is embodied as a coding switch comprising a plurality of resistor bodies according to one embodiment of the ambient-light intensity detector  100 , wherein the controller  70  is configured with the plurality of preset control scales by selecting or adjusting the resistance of different resistor bodies and coding the detecting values corresponding to the combination resistance of different resistor bodies of the BCD coding switch, such that the error of the controller  70  can be reduced effectively. The controller  70  comprises a control-scale selector  71  for actuating and switching between the different preset control scales of the controller  70  so as to adjust the detecting value of the photosensitive element  30 . 
     Preferably, the control-scale selector  71  is embodied as a rotation selector so as to minimize the size of the controller  70 . For example, the control-scale selector  71  has an indented groove  711  for enabling an actuation device to insert in the indented groove  711  and control the control-scale selector  71 . Selectively, the control-scale selector  71  can be driven by a driving unit such as a motor. 
     Furthermore, the housing  51  has an installing slot  515  formed at the surrounding wall of the housing  51  at the lower end  512  thereof, wherein the installing slot  515  is communicated with the receiving cavity  513 . The controller  70  is attached to the circuit board  60  and extends outwardly from the receiving cavity  513  of the housing  51  to install within the installing slot  515  of the housing  51 , such that the circuit board  60  is retained in the receiving cavity  513  of the housing  51 . After the controller  70  is installed in the housing, the control-scale selector  71  of the controller  70  is exposed to outside of the housing  51 , adapted for allowing the plurality of preset control scales of the controller  70  being actuated and selected for adjusting the detecting values of the photosensitive element  30 . 
     According to an alternative mode of the preferred embodiment of the ambient-light intensity detector  100  as shown in  FIG. 5A , the light-converging component  20  is embodied as a converging lens (plano-convex lens), wherein the detection light is converged to the light-converging path  40  via the light-converging component  20  when the detection light passes through the light-converging component from its light-entering surface (convex surface)  23  to the light-emerging surface (flat surface)  24 , and is received by the photosensitive element  30  at the photosensitive surface  31  thereof. 
     Alternatively, the light-converging component  20  can be embodied as a combined converging lens. In other words, the light-converging component  20  may comprises two or more converging lenses, wherein a gap may be formed between each two adjacent converging lenses or each two adjacent converging lenses, or that the two adjacent converging lenses are overlappedly attached with each other. 
     Referring to the  FIG. 5A  of the drawings, the light-entering surface  23  of the light-converging component  20  is embodied as a convex light-entering surface and the light-emerging surface  24  of the light-converging component  20  is embodied as a flat light-emerging surface for converging the detection light to the light-converging path  40 . Correspondingly, the light-inletting surface  13  of the light-uniforming component  10  is embodied as a convex light-inletting surface and the light-outletting surface  14  of the light-uniforming component  10  is a concave light-outletting surface in such a manner that the light-uniforming component  10  and the light-converging component  20  are matched with each other in shape and size correspondingly as shown in  FIG. 5A . 
     Preferably, the curvature of the light-inletting surface  13  and the curvature of the light-outletting surface  14  of the light-uniforming component  10  are consistent with the curvature of the light-entering surface  23  of the light-converging component  20 , such that the cross sections of the light-converging component  20  and the light-uniforming component  10  at any position along an axial direction are in centrosymmetric shape where their centers are located at the central axis  201  of the light-converging component  20 . Accordingly, the reflection light around the ambient-light intensity detector  100  is able to pass through the light-uniforming component  10  nonselectively and undistinguishably to form the pending detection light, and that the pending detection light is able to be converged to the light-converging path  40  by the light-converging component  20  nonselectively and undistinguishably, such that the accuracy of the ambient-light intensity detector  100  can be improved. 
     In addition, the ambient-light intensity detector  100  has a gap  101  provided between the light-outletting surface  14  of the light-uniforming component  10  and the light-entering surface  23  of the light-converging component  20 . In other words, the gap  101  of the ambient-light intensity detector  100  is defined between the light-outletting surface  14  of the light-uniforming component  10  and the light-entering surface  23  of the light-converging component  20 , such that the pending detection light emitted from the light-outletting surface  14  propagates through the gap  101  and enters the light-converging component  20  from its light-entering surface  23 , wherein gas (such as, but not limited to, air) is retained in the gap  101  for reducing energy-loss of the detection during the light is converged to the light-converging path  40  by the light-converging component  20 . Therefore, the accuracy of the light intensity detected by the ambient-light intensity detector  100  can further be improved. 
     Alternatively, the light-outletting surface  14  of the light-uniforming component  10  is overlappedly attached to the light-entering surface  23  of the light-converging component  20 . In other words, there is no gap  101  formed between the light-outletting surface  14  of the light-uniforming component  10  and the light-entering surface  23  of the light-converging component  20 . 
     Furthermore, the light-uniforming component  10  is provided in front of the light-entering surface  23  of the light-converging component  20 . In other words, the light-converging component  20  is installed first, and then the light-uniforming component  10  is installed by attaching to the light-entering surface  23  of the light-converging component  20  to avoid the gap  101  being formed between the light-outletting surface  14  of the light-uniforming component  10  and the light-entering surface  23  of the light-converging component  20 . 
     Referring to the  FIG. 5B  of the drawings, another alternative mode of the ambient-light intensity detector  100  is illustrated, wherein the structure and configuration of the ambient-light intensity detector  100  in this alternative mode is similar to that as shown in the  FIG. 5A , except that the light-emerging surface  24  of the light-converging component  20  is embodied as a concave light-emerging surface, and the curvature of the light-emerging surface  24  of the light-converging component  20  is smaller than that of the light-entering surface  23  of the light-converging component  20  for allowing the detection light being converged to the light-converging path  40  through the light-converging component  20 . 
     In other words, as shown in  FIG. 5B , the light-inletting surface  13  of the light-uniforming component  10  is embodied as a convex surface and the light-outletting surface  14  of the light-uniforming component  10  is embodied as a concave surface, while the light-entering surface  23  of the light-converging component  20  is a embodied as convex surface and the light-emerging surface  24  of the light-converging component  20  is embodied as a concave surface. The curvature of the light-entering surface  23  of the light-uniforming component  10  is consistent with the curvature of the light-outletting surface  14  of the light-uniforming component  10  and the curvature of the light-entering surface  23  of the light-converging component  20 , while the curvature of the light-emerging surface  24  of the light-converging component  20  is smaller than the curvature of the light-entering surface  23  of the light-converging component  20 . 
     Referring to the  FIG. 5C  of the drawings, another alternative mode of the ambient-light intensity detector  100  is illustrated, wherein the structure and configuration of the ambient-light intensity detector  100  in this alternative mode is similar to that as shown in the  FIG. 5A , except that the light-emerging surface  24  of the light-converging component  20  is a embodied as convex surface. I n other words, the light-inletting surface  13  of the light-uniforming component  10  is embodied as a convex surface and the light-outletting surface  14  of the light-uniforming component  10  is embodied as a concave surface, while the light-entering surface  23  of the light-converging component  20  is a convex light-entering surface and the light-emerging surface  24  of the light-converging component  20  is a convex light-emerging surface. 
     Referring to the  FIG. 5D  of the drawings, the light-inletting surface  13 , another alternative mode of the ambient-light intensity detector  100  is illustrated, wherein the structure and configuration of the ambient-light intensity detector  100  in this alternative mode is similar to that as shown in the  FIG. 5A , except that the light-outletting surface  14  of the light-uniforming component  10  and the light-entering surface  23  of the light-converging component  20  are flat surfaces, while the light-emerging surface  24  of the light-converging component  20  is a convex surface, such that the pending detection light, after emerging out from the light-outletting surface  14  of the light-uniforming component  10 , is converged to the light-converging path  40  through the light-converging component  20 . 
     Referring to the  FIG. 6  of the drawings, another alternative mode of the ambient-light intensity detector  100  is illustrated, wherein the structure and configuration of the ambient-light intensity detector  100  in this alternative mode is similar to that as shown in the  FIGS. 1-4 , except that no first installing ring  53  is provided at the enclosure  50 . More specifically, the enclosure  50  comprises the second installing ring  54  and two installing arms  55 , wherein the second installing ring  54  is installed on the housing  51  in such a manner that the threads of the inner wall of the second installing ring  54  are engaged with the threads of the outer wall of the housing  51 . Each of the installing arms  55  has an installing end  551  and an opposed free end  552 , wherein two installing arms  44  are mounted at two sides of the housing  51  symmetrically in such a manner that the installing end  551  of each of the installing arms  55  is mounted on the housing  51  at the lower end  512  thereof. A sandwiching space is formed between the two installing arms  55  and the second installing ring  54  so as to sandwich the stationary lighting fixture. Preferably, the installing end  551  of each of the installing arms  55  is mounted with a torsional-spring installing end for decreasing a size of the clamping space so as to securely retain the stationary lighting fixture in position. 
     Referring to the  FIG. 7A  of the drawings, a constant light system according to a preferred embodiment of the present invention is illustrated, wherein the constant light system comprises an ambient-light intensity detector  100 , one or more lighting fixtures  200  and a control system  300 . The ambient-light intensity detector  100  and the lighting fixtures  200  are electrically connected with the control system  300 , wherein the control system  300  is configured to selectively control the lighting fixtures  200  according to the detection result of the ambient-light intensity detector  100 . For example, the control system  300  is able to control the luminous intensity of the lighting fixtures  200  based on the detection result of the ambient-light intensity detector  100 , so as to maintain a constant ambient-light intensity in the use environment. 
     According to the preferred embodiment of the present invention, the ambient-light intensity detector  100  and the lighting fixtures  200  may be installed adjacent with each other at a ceiling, so as to retain the ambient-light intensity detector  100  and the lighting fixtures  200  in the use environment. 
     It is worth mentioning that the type of the control system  300  is not intended to be limiting the scope of the present invention. For example, the control system  300  may be embodied, but not limited to, a CPU (Central Processing Unit) installed at or being supported by the ceiling of the use environment so as to be retained in the use environment Alternatively, the control system  300  may not be retained in the use environment but arranged to receive the signal of the detection result of the ambient-light intensity detector  100  and send the control command to the lighting fixtures  200  through a communication network or other communication means, so as to control the illuminating condition of the one or more lighting fixtures  200  according to the detection result of the ambient-light intensity detector  100 . 
     Those skilled in the art would understand that the control system  300  is paired with the ambient-light intensity detector  100 . For example, when the controller  70  comprises a MCU (Microprogrammed Control Unit), such as a BDC code switch having a MCU, the control system  300  is configured as a controlling arrangement comprising a control interface such as PWM, 0/1-10V, DALi, I 2  C and so on, and that when the controller  70  is configured as a 0/1-10V controlling arrangement, the control system  300  is embodied as a controlling arrangement comprising a 0/1-10V control interface correspondingly. When the constant light system is electrically powered, the ambient-light intensity detector  100  detects to the ambient light intensity in the use environment continuously, wherein the controller  70  is arranged to send different control command signals based on the detection results obtained by the ambient-light intensity detector  100  and the control system  300  adjusts the luminous intensity of the lighting fixtures  200  according to the control command signals from the control system  300 , wherein when the detection result of the ambient-light intensity detector  100  is lower than the preset detecting value of the controller  70 , the one or more lighting fixtures  200  are adjusted to be brighter correspondingly. Instead, when the detection result of the ambient-light intensity detector  100  is greater than the preset detecting value of the controller  70 , the one or more lighting fixtures  200  are adjusted to be dimmer correspondingly. Accordingly, when the intensity of the pending detection light changes, being stronger or weaker, the control system  300  is able to adjust the luminous intensity of the one or more lighting fixtures  200  in accordance with the detection results of the ambient-light intensity detector  100  in a dynamic compensation manner so as to maintain a constant intensity of the ambient light in the use environment corresponding to the detecting value of the preset control scale. 
     Furthermore, it should not be limited in the scope of the present invention that whether the detecting value is correspondingly adjusted and preset by actuating a sliding potentiometer in a stepless manner directly or through selecting a resistance from different resistor bodies and a combination resistance of multiple resistors by actuating a dial coding switch. In other words, the controller  70  can be arranged as the sliding potentiometer for selecting different detecting values by adjusting to different resistance scale in a stepless manner, or be arranged as the dial coding switch for precisely selecting different detecting values by selecting different coding combinations of different resistors. In other words, the selection of different detecting values may be completed by other coding combination methods known in the art. For instance, the different detecting values may be selectively adjusted by the corresponding preset control scales generated in the MCU by the combination of the different I/O control interfaces thereof. Alternatively, the different detecting values may also be selectively adjusted by the values generated in the MCU and mapping with the corresponding detecting values, such that the selection of the detecting values can be implemented by a combination of the different I/O control interfaces and the corresponding control command is outputted for transmission via a wireless network or other communication means, which is not intended to be limiting in the present invention. 
     In other words, the controller  70  is arranged to provide a plurality of control scales corresponding to a plurality of detecting values respectively, wherein the correspondence relationship between each of the control scales and the detecting values is not intended to be limiting in the present invention. In one example, the controller  70  is able to be configured to adjust the detecting values in a stepless manner (i.e. the controller  70  is embodied as a sliding potentiometer) that the number of the preset control scales is not limited and the preset control scales corresponding to the detecting values are in functional relationship respectively. In one example, the controller  70  is able to be configured to adjust the detecting values in a level-to-level manner that the preset control scales corresponding to the detecting values are in list relationship respectively. For example, when the controller  70  is embodied as a dial coding switch, the different detecting values are selectively adjusted by switching the dial coding switch to different resistance positions corresponding to coding combination of different resistors in a level-to-level manner. When the controller  70  is embodied as a BDC coding switch comprising a plurality of resistors, and the different detecting values are selectively adjusted by selecting one or combining a group of different resistors. When the controller  70  is embodied as a MCU, the different detecting values are selectively adjusted by providing a preset control scale which is corresponding to a particular detecting value through the I/O control interfaces of the MCU. The preset control scale is communicatively transmitted to the controller  70  to control the controller  70  to select a different detecting value in a remote control manner or by a preset control algorithm, which is not intended to be limiting in the present invention. 
     It is worth mention that the control system  300  is integrated in the ambient-light intensity detector  100  in some examples according to the preferred embodiment of the present invention. 
     During the installation of the ambient-light intensity detector  100  in the use environment, the detecting range of the ambient-light intensity detector  100  can be selectively adjusted by changing a distance between the photosensitive surface  31  of the photosensitive element  30  of the ambient-light intensity detector  100  and the light-emerging surface  24  of the light-converging component  20 , so as to ensure the detecting range of the ambient-light intensity detector  100  matching with and being suitable to the corresponding use environment. 
     In addition, during the installation of the ambient-light intensity detector  100  in the use environment, the preset control scales of the controller  70  is selectively adjusted to adjust the detecting values of the photosensitive element  30  correspondingly, while the detecting values of the photosensitive element  30  are associated with the ambient-light intensity of the use environment. In other words, the detecting values of the photosensitive element  30  are corresponding to the different expected ambient light intensities of the use environment desired by a user. 
     According to the constant light system of the present invention, the ambient-light intensity detector  100  is able to detect the light intensity of the use environment in real-time, wherein the luminous intensity of the lighting fixtures  200  is dimmed in responsive to the detected ambient light intensity by the ambient-light intensity detector  100  that is greater than the expected detecting value of the use environment, wherein the luminous intensity of the lighting fixtures  200  is increased automatically in responsive to detected ambient light intensity by the ambient-light intensity detector  100  that is lower than the expected detecting value of the use environment. Accordingly, the ambient-light intensity of the use environment can always be maintained in constant. 
     Referring to the  FIG. 7B  of the drawings, a constant light system according to an alternative mode of the preferred embodiment of the present invention is illustrated, wherein the constant light system comprises a plurality of ambient-light intensity detectors  100 , a lighting fixture  200  and a control system  300 , wherein each of the ambient-light intensity detectors  100  and the lighting fixture  200  are electrically connected with the control system  300 , and the plurality of ambient-light intensity detectors  100  are installed at different positions of the use environment. The constant light system is able to detect a real ambient light intensity of the use environment by the plurality of ambient-light intensity detectors  100  at different positions of the use environment. 
     In order to enable the detection of a real ambient light intensity of the use environment, the detecting values of the photosensitive element  30  of the ambient-light intensity detectors  100  are required to be unified after the ambient-light intensity detectors  100  are installed in the use environment. The controller  70  of each of the ambient-light intensity detectors  100  of the constant light system of the present invention has a plurality of preset control scales, wherein the preset control scales of each of the controllers  70  are paired with the detecting values of the photosensitive elements  30  respectively and correspondingly, such that after the ambient-light intensity detectors  100  are installed in the use environment, the controllers  70  of the ambient-light intensity detectors  100  are adjusted to the same preset control scale so as to unify the detecting values of the photosensitive elements  30  of the ambient-light intensity detectors  100 , so as to ensure each of the ambient-light intensity detectors  100  detecting the real light intensity in the use environment. 
     Referring to the  FIG. 8A  to  FIG. 8C , an ambient-light intensity detector  100 A according to a second preferred embodiment of the present invention is illustrated, wherein the ambient-light intensity detector  100  comprises a light-uniforming component  10 A, a light-converging component  20 A, a photosensitive element  30 A, and a light-deflecting component  80 A, wherein the light-converging component  20 A defines a light-converging path  40 A. The light-uniforming component  10 A is retained in the light-converging path  40 A defined by the light-converging component  20 A and configured to uniformly and evenly mix the reflection lights reflected from one or more objects in a use environment (where the ambient-light intensity detector  100 A is applied) to form a pending detection light while the reflection lights passing through the light-uniforming component  10 A. The light-converging component  20 A is configured to converge the pending detection light to the light-converging path  40 A. The light-deflecting component  80 A is arranged in the light-converging path  40 A such that the propagation direction of the pending detection light can be changed in direction by means of the light-deflecting component  80 A after being converged to the light-converging path  40 A by the light-converging component  20 A. According to the second preferred embodiment of the present invention, the light-deflecting component  80 A is configured for deflecting the light-converging path  40 A at 90 degrees, such that the pending detection light, which is converged to the light-converging path  40 A by the light-converging component  20 A, continues to propagate after being deflected for 90 degrees. The photosensitive element  30 A has a photosensitive surface  31 A retained in the light-converging path  40 A defined by the light-converging component  20 A and is configured to receive the detection light after being converged to the light-converging path  40 A by the light-converging component  20 A and deflected by the light-deflecting component  80 A. The received detection light is then processed by the photosensitive element  30 A to detect the light intensity of the ambient-light in the use environment. 
     Accordingly, the ambient-light intensity detector  100 A is configured to uniformly and evenly mix the reflection lights reflected from one or more objects in the use environment through the light-uniforming component  10 A, such that the reflection lights lose their original propagation directions and form the pending detection light. Accordingly, the reflection lights reflected from the one or more objects are virtualized and the adverse effects to the detection accuracy caused by different surface reflectances of the one or more objects in the use environment can be reduced. 
     The ambient-light intensity detector  100 A is able to increase its detection range by converging and/or gathering the pending detection light to the light-converging path  40 A through the light-converging component  20 A, so as to enable the reflection lights reflected from more different types of objects passing through the light-uniforming component  10 A. Accordingly, the adverse effects to the detection accuracy caused by different surface reflectances of the objects in the use environment can be further reduced. 
     As shown in the  FIGS. 8A to 8C  of the drawings, the light-converging component  20 A of the ambient-light intensity detector  100 A is embodied as a light transmitting lens element which is capable of refracting and converging the pending detection light to the light-converging path  40 A after the pending detection light passes through the light-converging component  20 A. Accordingly, the light-converging component  20 A has an light entering side  21 A and an opposing light-emerging side  22 A, wherein the light-uniforming component  10 A is retained in the light-converging path  40 A at the light entering side  21 A of the light-converging component  20 A, wherein the light-deflecting component  80 A is retained in the light-converging path  40 A at the light-emerging side  22 A and the photosensitive surface  31 A of the photosensitive element  30  is retained in the light-converging path  40 A so as to ensure the reflection lights from one or more objects in the use environment being uniformly and evenly mixed by the light-uniforming component  10 A to form the pending detection light which is converged to the light-converging path  40 A after passing through the light-converging component  20 A and deflected by the light-deflecting component  80 A for being received by the photosensitive surface  31 A of the photosensitive element  30 A. 
     Preferably, the light-converging component  20 A is embodied as a Fresnel lens that the thickness and the manufacturing cost of the ambient-light intensity detector  100 A can be reduced. More specifically, the light-converging component  20 A has a light-entering surface  23 A and an opposing light-emerging surface  24 A, wherein the light-entering surface  23 A of the light-converging component  20 A is a side surface of the light entering side  21 A of the light-converging component  20  and has a plurality of protrusion tooth ripples in concentric circles. Correspondingly, the light-emerging surface  24 A of the light-converging component  20 A is a side surface of the light-emerging side  22 A of the light-converging component  20 A, wherein the light-emerging surface  24 A is a flat light-emerging surface. Accordingly, the pending detection light which enters the light-converging component  20 A from the light-entering surface  23 A of the light-converging component  20 A and emerges from the light-emerging surface  24 A of the light-converging component  20 A is converged to the light-converging path  40 A. 
     Furthermore, the light-converging component  20 A has a central axis  201 A, wherein the cross section of the light-converging component  20 A at any position along its axial direction is in a centrosymmetric shape and the symmetric center of which is located in the central axis  201 A of the light-converging component  20 A. Accordingly, the pending detection light formed from the ambient lights around the ambient-light intensity detector  100 A can be refracted and converged to the light converge path  40 A through the light-converging component  20 A nonselectively and undistingishably, such that the accuracy of the intensity of the light in the use environment being detected by the ambient-light intensity detector  100 A can be enhanced. 
     Preferably, the cross section of the light-uniforming component  10 A at any position along its axial direction is in a centrosymmetric shape and the symmetric center of which is located in the central axis  201 A of the light-converging component  20 A. Accordingly, the reflection lights around the ambient-light intensity detector  100 A can pass through the light-uniforming component  10 A nonselectively and undistinguishably for being uniformly and evenly mixed to from the pending detection light. 
     Referring to the  FIG. 8A-8C  of the drawings, the light-uniforming component  10 A has a light-inletting side  11 A and an opposing light-outletting side  12 A corresponding to the light-inletting side  11 A, wherein the light-uniforming component  10 A is retained in the light-converging path  40 A defined by the light-converging component  20 A while the light-outletting side  12 A of the light-uniforming component  10 A faces the light entering side  21 A of the light-converging component  20 A, so as to ensure the reflection lights reflected from the one or more objects in the use environment firstly entering the light-uniforming component  10 A from its light-inletting side  11 A and emerging from its light-outletting side  12 A, so that the reflection lights are uniformly and evenly mixed and/or diffused by the light-uniforming component  10 A to form the pending detection light. Then, the pending detection light enters the light-converging component  20 A from its light entering side  21 A and emerges from its light-emerging side  22 A, wherein the detection light is refracted and converged to the light-converging path  40 A through the light-converging component  20 A. 
     Furthermore, the light-uniforming component  10 A has a light-inletting surface  13 A and an opposing light-outletting surface  14 A corresponding to the light-inletting surface  13 A, wherein the light-inletting surface  13 A is a side surface of the light-inletting side  11 A of the light-uniforming component  10 A and, correspondingly, the light-outletting surface  14 A of the light-uniforming component  10 A is a side surface of the light-outletting side  12 A of the light-uniforming component  10 A. Accordingly, the reflection lights reflected from the one or more objects in the use environment enter the light-uniforming component  10 A from its light-inletting surface  13 A and emerge from its light-outletting surface  14 A to form the pending detection light. 
     It is worth mentioning that the type of the light-inletting surface  13 A and the light-outletting surface  14 A of the light-uniforming component  10 A is not intended to be limiting in the ambient-light intensity detector according to the preferred embodiment of the present invention. For example, both of the light-inletting surface  13 A and the light-outletting surface  14 A of the light-uniforming component  10 A can be embodied as smooth surfaces or rough surfaces. Alternatively, one of the light-inletting surface  13 A and the light-outletting surface  14 A is a smooth surface and the other is a rough surface. 
     It is worth mentioning that, although the light-inletting surface  13 A and the light-outletting surface  14 A of the light-uniforming component  10 A of the ambient-light intensity detector  100 A are embodied as flat surfaces as an example shown in the  FIGS. 8A to 8C  of the drawings according to the preferred embodiment, those who skilled in the art would understand that the description and features of the ambient-light intensity detector  100 A in this preferred embodiment as shown in the  FIGS. 8A to 8C  are not intended to limit the scope of the ambient-light intensity detector  100 A of the present invention. In other examples, both the light-inletting surface  13 A and the light-outletting surface  14 A of the light-uniforming component  10 A of the ambient-light intensity detector  100 A can be embodied as arc surfaces, such as either convex arc surface or concave arc surface. Alternatively, one of the light-inletting surface  13 A and the light-outletting surface  14 A of the light-uniforming component  10 A is embodied as a convex surface while the other is embodied as a concave surface. 
     Referring to the  FIGS. 8A to 8C  of the drawings, a gap  101 A is formed between the light-outletting surface  14 A of the light-uniforming component  10 A and the light-entering surface  23 A of the light-converging component  20 A. In other words, the ambient-light intensity detector  100 A has the gap  101 A defined between the light-uniforming component  10 A and the light-converging component  20 A. Accordingly, the pending detection light, exiting from the light-outletting surface  14 A of the light-uniforming component  10 A, propagates in the gap  101 A to enter the light-converging component  20 A from its light-entering surface  23 A, wherein gas, such as air, is retained in the gap  101 A for reducing the energy-loss of the pending detection light when being converged to the light-converging path  40 A through the light-converging component  20 A, so as to enhance the detection accuracy of the intensity of the light detected by the ambient-light intensity detector  100 A. 
     Alternatively, according to an alternative mode of the ambient-light intensity detector  100 A of the present invention, the light-outletting surface  14 A of the light-uniforming component  10 A can be overlappedly attached to the light-entering surface  23 A of the light-converging component, such that the pending detection light, emerging from the light-outletting surface  14 A of the light-uniforming component  10 A, directly enters the light-converging component  20 A from its light-entering surface  23 A. 
     Further referring to  FIG. 8A  to  FIG. 8C  of drawings of the present invention, the light-deflecting component  80 A is a light reflective element which can change the radiating direction of the pending detection light in a reflecting manner. In particular, the light-deflecting component  80 A has a deflecting surface  81 A, wherein the light-emerging surface  24 A of the light-converging component  20 A faces the deflecting surface  81 A of the light-deflecting component  80 A to define a light-inlet path between the deflecting surface  81 A of the light-deflecting component  80 A and the light-emerging surface  24 A of the light-converging component  20 A, wherein the photosensitive surface  31 A of the photosensitive element  30 A is arranged to face the deflecting surface  81 A of the light-deflecting component  80 A so as to define an light-outlet path between the photosensitive surface  31 A of the photosensitive element  30 A and the deflecting surface  81 A of the light-deflecting component  80 A, wherein the pending detection light, which enters from the light-emerging surface  24 A of the light-converging component  20 A, is reflected by the deflecting surface  81 A of the light-deflecting component  80 A and then is deflected after being propagated to the deflecting surface  81 A of the light-deflecting component  80 A along the light-inlet path. Then, the deflected light is propagated along the light-outlet path for being received by the photosensitive surface  31 A of the photosensitive element  30 A. 
     Preferably, according to the ambient-light intensity detector  100 A of this embodiment as illustrated in  FIGS. 8A to 8C , the light-emerging surface  24 A of the light-converging component  20 A is a flat light-emerging surface and the deflecting surface  81 A of the light-deflecting component  80 A is a flat reflecting surface, wherein the angle formed between the plane defined by the deflecting surface  81 A of the light-deflecting component  80  and the plane defined by the light-emerging surface  24 A of the light-converging component  20 A is 45 degrees. Correspondingly, the angle defined between a plane defined by the deflecting surface  81 A of the light-deflecting component  80  and the plane defined by the photosensitive surface  31 A of the photosensitive element  30 A is also 45 degrees, such that the pending detection light is deflected for 90 degrees by the light-deflecting component  80 A. 
     Alternatively, according to an alternative mode of the preferred embodiment of the ambient-light intensity detector  100 A, the deflecting surface  81 A is an arc surface. For example, the deflecting surface  81 A of the light-deflecting component  80 A is a concave arc surface so as to further converge the pending detection light while the deflecting surface  81 A is deflecting the pending detection light, or that the deflecting surface  81 A of the light-deflecting component  80 A is a convex arc surface so as to further converge the pending detection light while the deflecting surface  81 A is deflecting the pending detection light. 
     Alternatively, according to other preferred embodiments of the ambient-light intensity detector  100 A, the light-deflecting component  80 A is a refractive element for deflecting the radiating direction of the pending detection light. In particular, the light-deflecting component  80 A is retained at the out-light side  22 A of the light-converging component  20 A, wherein the light-inlet path is defined between the light-deflecting component  80 A and the light-emerging surface  24 A of the light-converging component  20 A, and the light-outlet path is defined between the light-deflecting component  80 A and the photosensitive surface  31 A of the photosensitive element  30 A, wherein the pending detection light, which emerges from the light-emerging surface  24 A of the light-converging component  20 A, is refracted and deflected after being propagated to the light-deflecting component  80 A along the light-inlet path, and the deflected light is propagated along the light-outlet path so as to being received by the photosensitive surface  31 A of the photosensitive element  30 A. 
     For example, the light-deflecting component  80 A is embodied as a prism adapted to change the propagation direction of the pending detection light by refraction. Or that, the light-deflecting component  80 A can be embodied as a prism combination, which is also adapted to change the propagation direction of the pending detection light by refraction. Alternatively, the light-deflecting component  80 A is embodied as a plane reflector adapted to change the propagation direction of the pending detection light by reflection. 
     Furthermore, referring to  FIGS. 8A to 8C , the ambient-light intensity detector  100 A according to this preferred embodiment of the present invention comprises an enclosure  50 A comprising a tubular housing  51 A, wherein the housing  51 A has an upper end  511 A, an opposing lower end  512 A and a receiving cavity  513 A extending from the lower end  512 A to the upper end  511 A. The light-uniforming component  10 A, the light-converging component  20 A and the light-deflecting component  80 A are retained within the receiving cavity  513 A of the housing  51 A along an axial direction defined in the housing  51 A. The photosensitive element  30 A is retained in the receiving cavity  513 A of the housing  51 A, wherein the housing  51 A defines a detection environment  102 A therein so as to avoid interference to the detection result of the ambient-light intensity detector  100 A by external light. 
     More specifically, the light-uniforming component  10 A is retained in the receiving cavity  513 A of the housing  51 A by mounting the sidewall of the light-uniforming component  10 A to an inner wall of the housing  51 A while the light-outletting surface  13 A of the light-uniforming component  10 A facing outside of the housing  51 A. The light-converging component  20 A is retained in the receiving cavity  513 A of the housing  51 A by mounting a sidewall of the light-converging component  20 A to the inner wall of the housing  51 A while the light entering side  21 A of the light-converging component  20 A facing the light-outletting side  12 A of the light-uniforming component  10 A. The light-deflecting component  80 A is installed at the inner wall of the housing  51 A while its deflecting surface  81 A facing the light-emerging side  22 A of the light-converging component  20 A, such that a light-inlet path is defined between the deflecting surface  81 A of the light-deflecting component  80 A and the light-emerging surface  24 A of the light-converging component  20 A. The photosensitive element  30 A is retained within the receiving cavity  513 A of the housing  51 A while the photosensitive surface  31 A of the photosensitive element  30 A faces the deflecting surface  81 A of the light-deflecting component  80 A, such that a light-outlet path is defined between the deflecting surface  81 A of the light-deflecting component  80 A and the photosensitive surface  31 A of the photosensitive element  30 A. During the detection of the intensity of the ambient light in the use environment by the ambient-light intensity detector  100 A, external light is blocked from entering the receiving cavity  513 A of the housing  51 A by the surrounding wall of the housing  51 A, so that only the light radiating towards the light-inletting side  11 A of the light-uniforming component  10 A is allowed to enter into the receiving cavity  513 A of the housing  51 A. Accordingly, the photosensitive surface  31 A of the photosensitive element  30 A is only allowed to receive and detect the pending detection light being converged to the light-converging path  40 A through the light-converging component  20 A, so as to avoid interference to the detection accuracy of the ambient-light intensity detector  100 A by the external light. 
     Alternatively, according to an alternative mode of the ambient-light intensity detector  100 A of the present invention, the light-deflecting component  80 A and the housing  51 A can be integrally formed. In other words, the deflecting surface  81 A is integrally formed by a portion of the inner wall of the housing  51 A. 
     Furthermore, referring to  FIGS. 8A to 8C , according to the preferred embodiment of the present invention, the ambient-light intensity detector  100 A comprises a circuit board  60 A retained within the receiving cavity  513 A of the housing  51 A, wherein the photosensitive element  30 A is attached to the circuit board  60 A and the photosensitive surface  31 A of the photosensitive element  30 A is arranged parallel to the circuit board  60 A, such that the photosensitive element is retained in the receiving cavity  513 A of the housing  51 A. 
     Preferably, the circuit board  60 A is extended in a direction consistent with the axial direction of the housing  51 A, such that the circuit board  60 A is extended along the axial direction of the housing  51 A and the plane defined by the photosensitive surface  31 A of the photosensitive element  30 A is parallel to the extending direction of the circuit board  60 A, so that an overlapped area between the photosensitive element  30 A and the circuit board  60 A can be increased so as to guarantee the stability of the position and angle of the photosensitive element  30 A. 
     The housing  51 A further comprises a cover  52 A having a through hole  521 A, wherein the receiving cavity  513 A of the housing  51 A is thoroughly extended from the lower end  512 A to the upper end  511 A of the housing  51 A, wherein after the circuit board  60 A is installed in the receiving cavity  513 A of the housing  51 A, the cover  52 A is mounted in the receiving cavity  513 A of the housing  51 A to enclose an upper opening of the receiving cavity  513 A of the housing  51 A, wherein an electric wiring is extended into the receiving cavity  513 A of the housing  51 A through the through hole  521 A of the cover  52 A fittingly to electrically connect to circuit board  60 A. 
     Furthermore, the housing  51 A has at least two engaging slots  514 A, formed in the surrounding wall of the housing  51 A at the upper end  511 A thereof, communicating with the receiving cavity  513 A. The cover  52 A further comprises a cover body  522 A, at least two mounting arms  523 A extended from the cover body  522 A, and at least two engaging protrusions  524 A protruded from free ends of the at least two mounting arms  523 A respectively. The cover  52 A is installed at the upper end  511 A of the housing  51 A by inserting the mounting arms  523 A of the cover  52 A into the upper opening of the receiving cavity  513 A of the housing  51 A and engaging the engaging protrusions  524 A of the cover  52 A into the engaging slots  514 A of the housing  51 A respectively and automatically due to the elasticity of the mounting arms  523 A, so as to enclose the upper opening of the receiving cavity  513 A of the housing by the cover  52 A. 
     As shown in the  FIGS. 8A to 8C  of the drawings, the enclosure  50 A further comprises a first installing ring  53 A and a second installing ring  54 A, wherein threads are provided at the inner walls of the first installing ring  53 A and second installing ring  54 A. Accordingly, the housing  51 A has a thread portion provided at the outer surrounding wall thereof, wherein the first installing ring  53 A is mounted on the housing  51 A by engaging the thread at the inner wall thereof with the thread portion at the outer surrounding wall of the housing  51 A. Similarly, the second installing ring  54 A is mounted on the housing  51 A by engaging the thread at the inner wall thereof with the thread portion at the outer surrounding wall of the housing  51 A. Therefore, the first installing ring  53 A and the second installing ring  54 A can incorporate with each other to install the ambient-light intensity detector  100 A to a stationary fixture. 
     For example, the stationary fixture can be a ceiling which has an installing hole, wherein the diameter of the outer surrounding wall of the housing  51 A is no less than the diameter of the installing hole of the stationary fixture and the diameters of the outer walls of the first installing ring  53 A and second installing ring  54 A are larger than the diameter of the installing hole of the stationary fixture. To mount the ambient-light intensity detector  100 A to the stationary fixture, the second installing ring  54 A is firstly mounted on the housing  51 A, the upper end  511 A of the housing  51 A is secondly aligned with and passes through the installing hole of the stationary fixture, and then the first installing ring  53 A is mounted on the housing  51 A thirdly. As such, the ambient-light intensity detector  100 A is installed to the stationary fixture in a manner that the stationary fixture is sandwichedly supported by the first installing ring  53 A and second installing ring  54 A mounted at two sides of the stationary fixture. 
     Alternatively, according to an alternative mode of ambient-light intensity detector  100 A of the preferred embodiment of the present invention, the first installing ring  53 A can be integrally formed on the housing  51 A, while the second installing ring  54  is mounted on the housing  51 A via a threaded joint means, or that the first installing ring  53 A is mounted on the housing  51 A via the threaded joint means while the second installing ring  54 A is integrally formed on the housing  51 A. 
     Furthermore, referring to  FIGS. 8A to 8C , the ambient-light intensity detector  100 A according to the preferred embodiment of the present invention comprises a controller  70 A which has a plurality of preset control scales for controlling the detecting values of the photosensitive element  30 A correspondingly, wherein the photosensitive element  30 A is controllably linked with the controller  70 A. In other words, the plurality of preset control scales of the controller  70 A is corresponding to the detecting values of the photosensitive element  30  respectively. In other words, the preset control scales of the controller  70 A have a one-to-one matching and corresponding relationship with the detecting values of the photosensitive element  30 A. 
     According to the preferred embodiment of the present invention, by configuring the controller  70 A to have the plurality of preset control scales, when the ambient-light intensity detector  100 A is enabled to adjust the controller  70 A to the same preset control scale in different time periods, the detecting value of the photosensitive element  30 A is maintained the same in consistence, thereby enhancing the controllability of the ambient-light intensity detector  100 A. For example, the preset control scales of the controller  70 A comprises “0-control scale”, “1-control scale”, “2-control scale”, “3-control scale”, “4-control scale”, “5-control scale”, “6-control scale”, “7-control scale”, “8-control scale”, “9-control scale”, “A-control scale”, “B-control scale”, “C-control scale”, “D-control scale”, “E-control scale”, and “F-control scale”, wherein when the controller  70 A is adjusted from the “A-control scale” to any other control scale and then returned back to the “A-control scale”, the detecting values of the photosensitive element  30 A while the controller  70 A is adjusted at the “A-control scale” for twice will be remained the same, such that the controllability of the ambient-light intensity detector  100 A is enhanced. 
     Accordingly, according to the preferred embodiment of the present invention, by providing the controller  70 A with the plurality of preset control scales, the ambient-light intensity detector  100 A is able to maintain a consistence of the detecting values of the photosensitive element  30 A, so as to enhance the controllability of the ambient-light intensity detector  100 A. For example, when two ambient-light intensity detectors  100 A are utilized in the use environment, the detecting values of the photosensitive elements  30 A of the two ambient-light intensity detectors  100 A are maintained the same after each of the controllers  70 A of the two ambient-light intensity detectors  100 A has been set at the “A-control scale”, such that the controllability of the ambient-light intensity detector  100 A is enhanced. 
     Preferably, the controller  70 A is embodied as a coding switch that enables the controller  70 A to be selectively switched among the preset control scales in a convenience manner. For example, according to the preferred embodiment of the ambient-light intensity detector  100 A of the present invention, the controller  70 A is embodied as a coding switch comprising a plurality of resistor bodies, wherein the controller  70 A is configured with the plurality of control scales by coding a combination relationship among the control scales, such that the error of the controller  70 A can be reduced effectively. The controller  70 A comprises a control-scale selector  71 A for actuating and switching the controller  70 A to different preset control scales for adjusting the detecting value of the photosensitive element  30 A. 
     Preferably, the control-scale selector  71 A is embodied as a rotation selector so as to reduce the size of the controller  70 A. For example, the control-scale selector  71 A has an indented groove  711 A for mounting an actuation device to control the control-scale selector  71 A. Selectively, the control-scale selector  71 A can be driven by a driving unit such as a motor. 
     Furthermore, the housing  51 A has an installing slot  515 A formed in the surrounding wall of the housing  51 A at the lower end  512 A of the housing  51 A and communicated with the receiving cavity  513 A. The controller  70 A is attached to the circuit board  60 A and extends outwardly from the receiving cavity  513 A of the housing  51 A to install in the installing slot  515 A of the housing  51 A, such that the circuit board  60 A is retained in the receiving cavity  513 A of the housing  51 A. After the controller  70 A is installed on the housing, the control-scale selector  71 A of the controller  70 A is arranged to be exposed outside the housing  51 A for allowing the plurality of preset control scales of the controller  70 A being actuated and selected so as to adjust the detecting values of the photosensitive element  30 A. 
     Referring to the  FIG. 9A  to  FIG. 9C , an ambient-light intensity detector according to a third preferred embodiment of the present invention is illustrated, wherein the ambient-light intensity detector  100 B comprises a light-uniforming component  10 B, a light-converging component  20 B and a photosensitive element  30 B. The light-converging component  20 B defines a light-converging path  40 B. The light-uniforming component  10 B is retained in the light-converging path  40 B defined by the light-converging component  20 B. The light-uniforming component  10 B is arranged to be retained for processing an uniform and even mixing of the reflection lights reflected from one or more objects in a use environment (where the ambient-light intensity detector  100 B is installed) to form a pending detection light while the reflection lights passing through the light-uniforming component  10 B. The light-converging component  20 B is configured to converge the pending detection light to the light-converging path  40 B. The photosensitive element  30 B has a photosensitive surface  31 B which is retained in the light-converging path  40 B defined by the light-converging component  20 B and configured to receive the pending detection light after being converged to the light-converging path  40 B by the light-converging component  20 B. The received detection light is then processed by the photosensitive element  30 B so as to detect the intensity of the ambient light in the use environment by detecting the pending detection light. 
     Accordingly, the ambient-light intensity detector  100 B is configured to uniformly and evenly mix the reflection lights reflected from one or more objects in the use environment through the light-uniforming component, such that the reflection lights lose their original propagation directions and form pending the detection light, such that the reflection lights are virtualized for reducing the adverse effects caused by different surface reflectances of the one or more objects in the use environment to the detection result of the ambient-light intensity detector  100 B. 
     Accordingly, the ambient-light intensity detector  100 B is able to increase its detection range by converging and/or gathering the pending detection light to the light-converging path  40 B by the light-converging component  20 B, that enables the reflection lights of more kinds of objects passing through the light-uniforming component  10 B, soas to reduce the adverse effects to the detection result caused by different surface reflectances of the one or more objects in the use environment. 
     Referring to  FIGS. 9A to 9C , according to the preferred embodiment of ambient-light intensity detector  100 B, the light-converging component  20 B is a light reflective element which has a concave light reflecting surface  25 B, wherein the photosensitive surface  31 B of the photosensitive element  30 B faces the concave light reflecting surface  25 B, wherein the pending detection light is converged to the light-converging path  40 B by the light-converging component  20 B in such a manner that the detection light emerged from the light-uniforming component  10 B is reflected by the concave light reflecting surface  25 B of the light-converging component  20 B, and then the pending detection light converged to the light-converging path  40 B is received by the photosensitive surface  31 B of the photosensitive element  30 B. 
     Furthermore, the light-uniforming component  10 B has a light-inletting side  11 B and an opposing light-outletting side  12 B corresponding to the light-inletting side  11 B, wherein the light-uniforming component  10 B is retained in the light-converging path  40 B defined by the light-converging component  20 B while the light-outletting side  12 B of the light-uniforming component  10 B faces the light entering side  21 B of the light-converging component  20 B, so as to ensure the reflection lights reflected from the one or more objects in the use environment enter the light-inletting side  11 B and emerge from the light-outletting side  12 B of the light-uniforming component  10 B, so as to uniformly and evenly mix and/or diffuse the reflection lights by the light-uniforming component  10 B to form the pending detection light. The pending detection light is then converged to the light-converging path  40 B by being reflected at the light reflecting surface  25 B of the light-converging component  20  for being received by the photosensitive surface  31 B of the photosensitive element  30 B. 
     In addition, the light-uniforming component  10 B has a light-inletting surface  13 B and an opposing light-outletting surface  14 B corresponding to the light-inletting surface  13 B, wherein the light-inletting surface  13 B of the light-uniforming component  10 B is a side surface of the light-inletting side  11 B of the light-uniforming component  10 B and, correspondingly, the light-outletting surface  14 B of the light-uniforming component  10 B is a side surface at the light-outletting side  12 B of the light-uniforming component  10 B. The reflection lights reflected from the one or more objects in the use environment enter the light-uniforming component  10 B from its light-inletting surface  13 B and emerge from its light-outletting surface  14 B to form the pending detection light while passing through the light-uniforming component  10 B. 
     It is worth mentioning that the type of the light-inletting surface  13 B and the light-outletting surface  14 B of the light-uniforming component  10 B is not intended to be limiting the scope of the ambient-light intensity detector  100 B according to the preferred embodiment of the present invention. For example, both of the light-inletting surface  13 B and the light-outletting surface  14 B of the light-uniforming component  10 B can be embodied as smooth surfaces or rough surfaces. Alternatively, the types of light-inletting surface  13 B and the light-outletting surface  14 B can be different, that is one of the light-inletting surface  13 B and the light-outletting surface  14 B of the light-uniforming component  10 B is a smooth surface while the other is a rough surface 
     It is worth mentioning that, although the light-inletting surface  13 B and the light-outletting surface  14 B of the light-uniforming component  10 B are embodied as flat surfaces as an example shown in the  FIGS. 9A to 9C  of the drawings according to the preferred embodiment, those who skilled in the art would understand that the description and features of the ambient-light intensity detector  100 B in this preferred embodiment as shown in the  FIGS. 9A to 9C  are not intended to limit the scope of the ambient-light intensity detector  100 B of the present invention. In some examples, both the light-inletting surface  13 B and the light-outletting surface  14 B of the light-uniforming component  10 B can be embodied as arc surfaces, either convex arc surface or concave arc surface. Alternatively, one of the light-inletting surface  13 B and the light-outletting surface  14 B of the light-uniforming component  10 B is embodied as a convex surface while the other is embodied as a concave surface. 
     In addition, according to the preferred embodiment of the present invention as shown in the  FIGS. 9A to 9C  of the drawings, the ambient-light intensity detector  100 B comprises an enclosure  50 B comprising a tubular housing  51 B, wherein the housing  51 B has an upper end  511 B, an opposed lower end  512 B, and a receiving cavity  513 B extending from the lower end  512 B to the upper end  511 B, wherein the light-uniforming component  10 B, the light-converging component  20 B and the photosensitive element  30 B are retained within the receiving cavity  513 B of the housing  51 B along an axial direction defined in the housing  51 B so as to define a detection environment  102 B within the tubular housing  51 B in order to avoid interference to the detection result of the ambient-light intensity detector  100 B by the external light. 
     More specifically, the light-uniforming component  10 B is retained in the receiving cavity  513 B of the housing  51 B by mounting a sidewall of the light-uniforming component  10 B to an inner wall of the housing  51 B, while the light-inletting side  11 B of the light-uniforming component  10 B is arranged to face outside of the housing  51 B. The light-converging component  20 B is retained in the receiving cavity  513 B of the housing  51 B by mounting a sidewall of the light-converging component  20 B to the inner wall of the housing  51 B. The photosensitive element  30 B is suspendedly retained in the receiving cavity  513 B of the housing  51 B with its photosensitive surface  31 B facing the light reflecting surface  25 B of the light-converging component  20 B, wherein a central axis  201 B of the light-converging component  20 B passes through a center of the photosensitive surface  31 B of the photosensitive element  30 B. When the ambient-light intensity detector  100 B is detecting the intensity of the ambient-light in the use environment thereof, external light is blocked from entering the receiving cavity  513 B of the housing  51 B by the surrounding wall of the housing  51 B, wherein only the light radiating towards the light-inletting side  11 B of the light-uniforming component  10 B is allowed to enter into the receiving cavity  513 B of the housing  51 B through the light-uniforming component  10 B, such that the pending detection light which is converged by the light-converging component  20 B is allowed to be only received and detected by the photosensitive surface  31 B of the photosensitive element  30 B, so as to avoid interference to the detection result of the ambient-light intensity detector  100 B by the external light. 
     Furthermore, referring to  FIGS. 9A to 9C , according to the preferred embodiment of the present invention, the ambient-light intensity detector  100 B comprises a circuit board  60 B retained in the receiving cavity  513 B of the housing  51 B, wherein the photosensitive element  30 B is attached to the circuit board  60 B such that the photosensitive element is suspendedly retained in the receiving cavity  513 B of the housing  51 B. 
     Preferably, the circuit board  60 B is extended in a direction consistent with the axial direction of the housing  51 B, that is the circuit board  60 B is extended along the axial direction of the housing  51 B and the plane defined by the photosensitive surface  31 B of the photosensitive element  30 B is perpendicular to the extending direction of the circuit board  60 B, such that the photosensitive surface  31 B of the photosensitive element  30 B and the circuit board  60 B are extended perpendicular with each other so as to ensure the photosensitive surface  31 B of the photosensitive element  30 B facing the light reflecting surface  25 B of the light-converging component  20 B. Alternatively, the extending direction of the circuit board  60 B is perpendicular to the axial direction of the housing  51 B, and the plane defined by the photosensitive surface  31 B of the photosensitive element  30 B is parallel to the extending direction of the circuit board  60 B, so as to ensure the photosensitive surface  31 B of the photosensitive element  30 B facing the light reflecting surface  25 B of the light-converging component  20 B. 
     The housing  51 B further comprises a cover  52 B having a through hole  521 B, wherein the receiving cavity  513 B of the housing  51 B is thoroughly extended from the lower end  512 B to the upper end  511 B thereof, wherein after the circuit board  60 B is installed in the receiving cavity  513 B of the housing  51 B, the cover  52 B is mounted at the receiving cavity  513 B of the housing  51 B to enclose an upper opening of the receiving cavity  513 B of the housing  51 B and an electric wiring is extended into the receiving cavity  513 B of the housing  51 B and electrically connected to circuit board  60 B through the through hole  521 B of the cover  52 B fittingly. 
     Furthermore, the housing  51 B has at least two engaging slots  514 B, formed in the surrounding wall of the housing  51 B at the upper end  511 B thereof, communicating with the receiving cavity  513 B. The cover  52 B comprises a cover body  522 B, at least two mounting arms  523 B extended from the cover body  522 B, and at least two engaging protrusions  524 B protruded from two opposing sides of a free end of each mounting arm  523 B. The cover  52 B is installed at the upper end  511 B of the housing  51 B by inserting the mounting arms  523 B of the cover  52 B into the upper opening of the receiving cavity  513 B of the housing  51 B and engaging the engaging protrusions  524 B of the cover  52 B into the engaging slots  514 B of the housing  51 B respectively and automatically due to the elasticity of the mounting arms  523 B, so as to enclose the upper opening of the receiving cavity  513 B of the housing by the cover  52 B. 
     As shown in the  FIGS. 9A to 9C  of the drawings, the enclosure  50 B further comprises a first installing ring  53 B and a second installing ring  54 B, wherein threads are formed at the inner walls of the first installing ring  53 B and second installing ring  54 B. Accordingly, the housing  51 B has a thread portion provided on the outer surrounding wall thereof, wherein the first installing ring  53 B is mounted on the housing  51 B by engaging its thread at the inner wall thereof with the thread portion at the outer surrounding wall of the housing  51 B. Similarly, the second installing ring  54 B is mounted on the housing  51 B by engaging the thread at the inner wall thereof with the thread portion at the outer surrounding wall of the housing  51 B. Therefore, the first installing ring  53 B and the second installing ring  54 B can incorporate with each other to install the ambient-light intensity detector  100 B to a stationary fixture. 
     For instance, the stationary fixture can be a ceiling which has an installing hole, wherein the diameter of the outer surrounding wall of the housing  51 B is no less than the diameter of the stationary fixture and the diameters of the outer walls of the first installing ring  53 B and second installing ring  54 B are larger than the diameter of the stationary fixture. To mount the ambient-light intensity detector  100 B to the stationary fixture, the second installing ring  54 B is firstly mounted on the housing  51 B, the upper end  511 B of the housing  51 B is aligned with and passes through the installing hole of the stationary fixture secondly, and then the first installing ring  53 B is mounted on the housing  51 B thirdly. As such, the ambient-light intensity detector  100 B is installed to the stationary fixture in a manner that the stationary fixture is sandwichedly supported by the first installing ring  53 B and the second installing ring  54 B mounted at two sides of the stationary fixture. 
     Alternatively, according to an alternative mode of the preferred embodiment of the present invention, the first installing ring  53 B can be integrally formed on the housing  51 B while the second installing ring  54 B is mounted on the housing  51 B by a threaded joint means, or that the first installing ring  53 B is mounted on the housing  51 B by the threaded joint means while the second installing ring  54 B is integrally formed on the housing  51 B. 
     In addition, referring to  FIGS. 9A to 9C , the ambient-light intensity detector  100 B according to the preferred embodiment of the present invention comprises a controller  70 B which is controllably linked to the photosensitive element  30 B and provided with a plurality of preset control scales for controlling the detecting values of the photosensitive element  30 B. In other words, the plurality of preset control scales of the controller  70 B is corresponding with the different detecting values of the photosensitive element  30  respectively, that is the preset control scales of the controller  70 B have a one-to-one matching and corresponding relationship with the detecting values of the photosensitive element  30 B. 
     According to the ambient-light intensity detector  100 B of the third preferred embodiment of the present invention, since the controller  70 A is provided with the plurality of preset control scales, the ambient-light intensity detector  100 B is capable of adjusting the controller  70 A to the same preset control scale in different time periods to maintain a consistence of the detecting values of the photosensitive element  30 B, thereby enhancing the controllability of the ambient-light intensity detector  100 B. For example, the preset control scales of the controller  70 B include “ 0 -control scale”, “1-control scale”, “2-control scale”, “3-control scale”, “4-control scale”, “5-control scale”, “6-control scale”, “7-control scale”, “8-control scale”, “9-control scale”, “A-control scale”, “B-control scale”, “C-control scale”, “D-control scale”, “E-control scale”, and “F-control scale”, wherein when the controller  70 B is adjusted from the “A-control scale” to any other control scale and then returned back to the “A-control scale”, the detecting value of the photosensitive element  30 B will be remained the same at the “A-control scale” for twice, such that the controllability of the ambient-light intensity detector  100 B is enhanced. 
     According to the ambient-light intensity detector  100 B of the third preferred embodiment of the present invention, by configuring the controller  70 B to have the plurality of preset control scales, the ambient-light intensity detector  100 B is able to maintain the same detecting value for the photosensitive element  30 B, so as to enhance the controllability of the ambient-light intensity detector  100 B. For example, when two ambient-light intensity detectors  100 B are utilized in the use environment, the detecting values of the photosensitive elements  30 B of the two ambient-light intensity detectors  100 B are consistence with each other when the controllers  70 B of the two ambient-light intensity detector  100 B are set to the same preset control-scale such as the “A-control scales”, such that the controllability of the ambient-light intensity detector  100 B is enhanced. 
     Preferably, the controller  70 B is embodied as a coding switch for ease to selectively switch among the preset control scales. In one example, the controller  70 B of the ambient-light intensity detector  100 B comprises a plurality of resistor bodies, wherein the controller  70 B is configured with the plurality of control scales by selecting or adjusting the resistance of different resistor bodies or coding a combination relationship of the resistor bodies, so that the error of the controller  70 B can be reduced effectively. The controller  70 B comprises a control-scale selector  71 B for actuating and switching the controller  70 B to different preset control scales for adjusting the detecting value of the photosensitive element  30 B. 
     Preferably, the control-scale selector  71 B is embodied as a rotation selector to reduce the size of the controller  70 B. For example, the control-scale selector  71 B has an indented groove  711 B for mounting an actuation device to control the control-scale selector  71 B. Selectively, the control-scale selector  71 B can be driven by a driving unit such as a motor. 
     In addition, the housing  51 B has an installing slot  515 B formed in the surrounding wall of the housing  51 B at the lower end  512 B thereof, wherein the installing slot  515 B is communicated with the receiving cavity  513 B. The controller  70 B is attached to the circuit board  60 B and installed in the installing slot  515 B while extending outside of the receiving cavity  513 B of the housing  51 B, such that the circuit board  60 B is retained in the receiving cavity  513 B of the housing  51 B. After the controller  70 B is installed on the housing  51 B, the control-scale selector  71 B of the controller  70 B is exposed outside of the housing  51 B, for allowing the plurality of preset control scales of the controller  70 B being actuated and selected for adjusting the detecting values of the photosensitive element  30 B. 
     According to the present invention, the foregoing and other objects and advantages are attained by a method of detecting a light intensity of an ambient-light, comprising the steps of: 
     (A) enabling at least a reflection light which is reflected from at least one object in a use environment to lose an original propagation direction thereof to form a pending detection light; 
     (B) converging the pending detection light to a light-converging path; and 
     (C) receiving and analyzing the pending detection light at a photosensitive surface of a photosensitive element retained in the light-converging path for detecting the light intensity of the ambient-light in the use environment. 
     In particular, in the step (A), the reflection light reflected from the object in the use environment is enabled to pass through the light-uniforming component  10  which makes the reflection light reflected from the object losing the original propagation direction thereof to form the pending detection light. 
     In the step (B), the pending detection light is converged to the light-converging path  40  by refracting the pending detection light, or that the pending detection light is converged to the light-converging path  40  by or reflecting the pending detection light. 
     According to the present invention, the foregoing and other objects and advantages are attained by a manufacturing method of an ambient-light intensity detector, comprising the steps of: 
     (a) installing a light-uniforming component  10  and a light-converging component  20  in a receiving cavity  513  of a housing  51 ; and 
     (b) installing a circuit board  60  with a photosensitive element  30  attached thereto in the receiving cavity  513  of the housing  51  at an upper end  511  thereof, wherein a photosensitive surface  31  of the photosensitive element  30  is retained in a light-converging path  20  defined by the light-converging component  20 . 
     In particular, the light-converging component  20  and the uniforming component  10  are installed in sequence in the receiving cavity  513  of the housing  51  from a lower end  512  of the housing  51  so as to configure the light-converging component  20  and the uniforming component  10  in the receiving cavity  513  of the housing  51 . In other words, the housing  51 , the light-converging component  20  and the light-uniforming component  10  are pre-made, wherein the light-converging component  20  is installed within the receiving cavity  513  of the housing  51  from the lower end  512  thereof firstly, and then the light-uniforming component  10  is installed within the receiving cavity  513  of the housing  51  from the lower end  512  thereof while keeping a light-inletting surface  13  of the light-uniforming component  10  being exposed to the outside of the housing  51 . 
     Alternatively, according to another preferred embodiment of manufacturing method of the present invention, the light-converging component  20  can be firstly formed in the receiving cavity  513  of the housing  51 , and then the light-uniforming component  10  is mounted in the receiving cavity  513  of the housing  51  at the lower end  512  thereof. In other words, the housing  51  integrally forms the light-converging component  20  in the receiving cavity  513  of the housing  51  and the light-uniforming component  10  is pre-made, so that after the light-converging component  20  is formed in the receiving cavity  513  of the housing  51 , the light-uniforming component  10  is installed in the receiving cavity  513  of the housing  51  from the lower end  512  thereof while allowing the light-inletting surface  13  of the light-uniforming component  10  being exposed to an external of the housing  51 . 
     Moreover, the step (b) further comprises the steps of: 
     (b.1) mounting a controller  70 , which has a plurality of preset control scales, to the circuit board  60  and controllably linking the photosensitive element  30  with the controller  70 ; and 
     (b.2) after the circuit board  60  is installed in the receiving cavity  513  of the housing  51 , allowing a control-scale selector  71  of the controller  70  to be exposed to the external of the housing  51  through a mounting slot communicating with the receiving cavity  513  of the housing  51 . 
     One skilled in the art will understand that the embodiment of the present invention as shown in the drawings and described above is exemplary only and not intended to be limiting. 
     It will thus be seen that the objects of the present invention have been fully and effectively accomplished. The embodiments have been shown and described for the purposes of illustrating the functional and structural principles of the present invention and is subject to change without departure from such principles. Therefore, this invention includes all modifications encompassed within the spirit and scope of the following claims.