Patent Publication Number: US-11644173-B2

Title: Lamp for vehicle and vehicle including the same

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of priority to Korean Patent Application No. 10-2021-0095663 filed in the Korean Intellectual Property Office on Jul. 21, 2021, the entire content of which is incorporated herein by reference. 
     BACKGROUND 
     1. Technical Field 
     The present disclosure relates to a lamp for a vehicle and a vehicle including the same, and more particularly, to a lamp for a vehicle, which is capable of implementing various types of light distribution patterns, and a vehicle including the same. 
     2. Discussion of Related Art 
     Lamps mounted in a vehicle to display predetermined information on a road surface are broadly classified into a reflection-type lamp including a reflector such as a multi-facet reflector (MFR) and a projection-type lamp including a mask member having through-holes having predetermined shapes. 
     However, in the related art, the reflection-type lamp has a large size and thus is not suitable for the trend of miniaturization. Further, the reflection type lamp may implement only a light distribution pattern having a simple shape such as a quadrangular shape. In addition, in the related art, the projection-type lamp may implement only a light distribution pattern corresponding to the shapes of the through-holes of the mask member. However, the projection-type lamp cannot implement a dynamic light distribution pattern. 
     SUMMARY 
     The present disclosure has been made in an effort to provide a lamp for a vehicle, which is capable of implementing a dynamic light distribution pattern while reducing a size of a lamp. 
     An exemplary embodiment of the present disclosure provides a lamp for a vehicle, the lamp including: a light source configured to emit light; and a pattern conversion unit disposed forward of the light source and configured to form two or more types of light distribution patterns by receiving the light emitted from the light source, in which the pattern conversion unit includes: a light-transmitting member disposed to face the light source and configured to transmit the light emitted from the light source; and a polymer dispersed liquid crystal (PDLC) member provided to be in close contact with one surface of the light-transmitting member. 
     The PDLC member may be attached to the light-transmitting member. 
     The PDLC member may be provided to be in close contact with a front surface of the light-transmitting member. 
     The pattern conversion unit may form the two or more types of light distribution patterns as light transmittance of the PDLC member is controlled by electric current applied to the PDLC member. 
     The PDLC member may include a first region and a second region, and the PDLC member may be controlled by a first-first step of applying electric current so that only the first region of the PDLC member transmits light for a first-first time, and a first-second step of applying electric current so that only the first region and the second region of the PDLC member transmit light for a first-second time after the first-first time. 
     The PDLC member may further include a third region, and the PDLC member may be controlled by the first-first step, the first-second step, and a first-third step of applying electric current so that only the first region, the second region, and the third region of the PDLC member transmit light for a first-third time after the first-second time. 
     The PDLC member may be provided in plural, and the PDLC members may include: a first PDLC member; and a second PDLC member provided to be in close contact with a front or rear surface of the first PDLC member. 
     The PDLC members may be controlled by a second-first step of applying electric current so that the entire region of the second PDLC member transmits light and only a partial region of the first PDLC member transmits light for a second-first time. 
     The PDLC members may further include a third PDLC member provided to be in close contact with a front or rear surface of the second PDLC member, and the PDLC members may be controlled by the second-first step, and a second-second step of applying electric current so that the entire region of the first PDLC member and the entire region of the third PDLC member transmit light and only a partial region of the second PDLC member transmits light for a second-second time after the second-first time. 
     The PDLC members may be controlled by the second-first step, the second-second step, and a second-third step of applying electric current so that the entire region of the first PDLC member and the entire region of the second PDLC member transmit light and only a partial region of the third PDLC member transmits light for a second-third time after the second-second time. 
     The lamp may further include: a collimator disposed between the light source and the pattern conversion unit; and a projection lens unit disposed forward of the pattern conversion unit. 
     Another exemplary embodiment of the present disclosure provides a vehicle including: a lamp for a vehicle, in which the lamp includes: a light source configured to emit light; and a pattern conversion unit disposed forward of the light source and configured to form two or more types of light distribution patterns by receiving the light emitted from the light source, and in which the pattern conversion unit includes: a light-transmitting member disposed to face the light source and configured to transmit the light emitted from the light source; and a polymer dispersed liquid crystal (PDLC) member provided to be in close contact with one surface of the light-transmitting member. 
     The lamp may be a backup guide lamp, a turn-signal lamp, or a welcome guide lamp. 
     According to the present disclosure, it is possible to provide the lamp for a vehicle, which is capable of implementing a dynamic light distribution pattern while reducing a size of the lamp. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a side view illustrating a structure of a lamp for a vehicle according to the present disclosure. 
         FIG.  2    is a cross-sectional view illustrating a structure of a pattern conversion unit of the lamp for a vehicle according to the present disclosure. 
         FIG.  3    is a view illustrating a state in which a PDLC member of the lamp for a vehicle according to the present disclosure transmits light in a first-first step. 
         FIG.  4    is a view illustrating a state in which the PDLC member of the lamp for a vehicle according to the present disclosure transmits light in a first-second step. 
         FIG.  5    is a view illustrating a state in which the PDLC member of the lamp for a vehicle according to the present disclosure transmits light in a first-third step. 
         FIG.  6    is a view illustrating a state in which the PDLC member of the lamp for a vehicle according to the present disclosure transmits light in a second-first step. 
         FIG.  7    is a view illustrating a state in which the PDLC member of the lamp for a vehicle according to the present disclosure transmits light in a second-second step. 
         FIG.  8    is a view illustrating a state in which the PDLC member of the lamp for a vehicle according to the present disclosure transmits light in a second-third step. 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, a lamp for a vehicle and a vehicle according to the present disclosure will be described with reference to the drawings. 
     Lamp for Vehicle 
       FIG.  1    is a side view illustrating a structure of a lamp for a vehicle according to the present disclosure, and  FIG.  2    is a cross-sectional view illustrating a structure of a pattern conversion unit of the lamp for a vehicle according to the present disclosure. 
     Referring to  FIGS.  1  and  2   , a lamp  10  for a vehicle (hereinafter, referred to as a ‘lamp’) according to the present disclosure may include: a light source  100  configured to emit light; a pattern conversion unit  200  disposed in front of the light source  100  and configured such that the light emitted from the light source  100  enters the pattern conversion unit  200 ; a collimator  300  disposed between the light source  100  and the pattern conversion unit  200 ; and a projection lens unit  400  disposed in front of the pattern conversion unit  200 . 
     The collimator  300  may be configured to convert the light emitted from the light source  100  into parallel light and transmit the parallel light. The description of the configuration of the collimator  300  and the principle of the collimator  300  producing the parallel light may be replaced with the publicly-known contents in the related art. 
     According to the present disclosure, the light, which exits the collimator  300  and enters the pattern conversion unit  200 , may be converted into light with a light distribution pattern having a predetermined shape by the pattern conversion unit  200 , and then the light may enter the projection lens unit  400 . In particular, according to the present disclosure, the pattern conversion unit  200  may form a plurality of light distribution patterns of a plurality of types. As described below, according to the present disclosure, it is possible to implement various and dynamic light distribution patterns by controlling electric current to be applied to the pattern conversion unit  200 . 
     The projection lens unit  400  may include a first lens  410  disposed in front of the pattern conversion unit  200 , and a second lens  420  disposed in front of the first lens  410 . For example, the light distribution pattern formed by the light exiting the pattern conversion unit  200  is enlarged or reduced by the first lens  410  and the second lens  420  and then displayed on the outside. The first lens  410  and the second lens  420  may each be an aspherical lens, but the type of lens is not limited thereto. 
     Referring to  FIGS.  1  and  2   , the pattern conversion unit  200  may include: a light-transmitting member  210  disposed to face the light source  100  with the collimator  300  interposed therebetween, the light-transmitting member  210  being configured to transmit the light emitted from the light source  100 ; and a polymer dispersed liquid crystal (PDLC) member  220  provided to be in contact with one surface of the light-transmitting member  210 . More particularly, the PDLC member  220  may be attached to the light-transmitting member  210 . 
     The light-transmitting member  210  may be configured to support the PDLC member  220 . That is, the PDLC member  220  may be provided in the form of a film having a small thickness. Since the PDLC member  220  is provided to be in contact with the light-transmitting member  210 , the PDLC member  220  may be kept fixed in a predetermined shape. 
     As described above, the light-transmitting member  210  is configured to support the PDLC member  220  without contributing to the formation of the light distribution pattern. Therefore, it is necessary to minimize the influence on the light distribution pattern formed on the outside by the lamp  10  according to the present disclosure. To this end, the light-transmitting member  210  may be made of a material excellent in light transmissivity. For example, the light-transmitting member  210  may be made of glass, polycarbonate, or acrylic. 
     Meanwhile,  FIG.  2    illustrates that the PDLC member  220  is provided to be in contact with a front surface of the light-transmitting member  210 , such that a distance between the PDLC member  220  and the light source  100  is longer than a distance between the light-transmitting member  210  and the light source  100 . However, alternatively, the PDLC member  220  may be provided to be in contact with a rear surface of the light-transmitting member  210 . In this case, a distance between the PDLC member  220  and the light source  100  may be shorter than a distance between the light-transmitting member  210  and the light source  100 . 
     The PDLC has a structure in which polymer and liquid crystal are mixed at a predetermined ratio between two sheets, i.e., an ITO film and a PET film. The PDLC becomes transparent or opaque depending on whether electric current is applied. That is, the PDLC is in an opaque state in a state in which no electric current is applied to the PDLC. When electric current is applied to the PDLC, the PDLC becomes transparent. 
     Based on the above-mentioned description, the pattern conversion unit  200  of the lamp  10  according to the present disclosure may form the light distribution patterns of the plurality of types as light transmittance of the PDLC member  220  is controlled by electric current applied to the PDLC member  220 . Therefore, according to the present disclosure, whether to transmit the light emitted from the light source  100  may be adjusted by controlling the electric current applied to the PDLC member  220 . Therefore, it is possible to implement various types of light distribution patterns and implement a light distribution pattern of a dynamic image that changes over time. 
     Meanwhile, the lamp  10  according to the present disclosure may be a backup guide lamp, a turn-signal lamp, or a welcome guide lamp. In particular, according to the present disclosure, it is possible to implement a light distribution pattern of a dynamic image that changes over time. Hereinafter, a method of implementing a light distribution pattern of a dynamic image by using the lamp according to the present disclosure will be described. 
       FIG.  3    is a view illustrating a state in which the PDLC member of the lamp for a vehicle according to the present disclosure transmits light in a first-first step, and  FIG.  4    is a view illustrating a state in which the PDLC member of the lamp for a vehicle according to the present disclosure transmits light in a first-second step. In addition,  FIG.  5    is a view illustrating a state in which the PDLC member of the lamp for a vehicle according to the present disclosure transmits light in a first-third step. 
     Referring to  FIGS.  3  to  5   , the PDLC member  220  of the lamp according to the present disclosure may be divided into a plurality of regions. In this case, whether to apply electric current to the plurality of regions may be independently controlled. For example, the PDLC member  220  may be divided into nine regions disposed in three rows and three columns. 
     For example, the PDLC member  220  may include a first region  221 , a second region  222 , and a third region  223 . 
     In this case, according to the present disclosure, the PDLC member  220  may be controlled by a first-first step (see  FIG.  3   ) of applying the electric current so that only the first region  221  of the PDLC member  220  transmits the light for a first-first time (first time period), a first-second step (see  FIG.  4   ) of applying the electric current so that the only the first region  221  and the second region  222  of the PDLC member  220  transmit the light for a first-second time (second time period) after the first-first time, and a first-third step of applying the electric current so that only the first region  221 , the second region  222 , and the third region  223  of the PDLC member  220  transmit the light for a first-third time (third time period) after the first-second time. In this case, as illustrated in  FIGS.  3  to  5   , a light distribution pattern, in which triangular light distribution patterns are arranged in one direction as the number of triangular light distribution patterns increases by one as time elapses, may be formed on the road surface. Therefore, according to the present disclosure, the shape of the light distribution pattern may change over time, thereby implementing the dynamic light distribution pattern. 
       FIG.  6    is a view illustrating a state in which the PDLC member of the lamp for a vehicle according to the present disclosure transmits light in a second-first step, and  FIG.  7    is a view illustrating a state in which the PDLC member of the lamp for a vehicle according to the present disclosure transmits light in a second-second step. In addition,  FIG.  8    is a view illustrating a state in which the PDLC member of the lamp for a vehicle according to the present disclosure transmits light in a second-third step. 
     As illustrated in  FIGS.  2 ,  6 ,  7 , and  8   , the PDLC member  220  may be provided in plural. For example, the PDLC members  220  may include a first PDLC member  220 - 1 , and a second PDLC member  220 - 2  provided to be in contact with a front or rear surface of the first PDLC member  220 - 1 . In the case in which the PDLC member  220  is provided to be in contact with the front surface of the light-transmitting member  210 , the first PDLC member  220 - 1  may be attached to the front surface of the light-transmitting member  210 , and the second PDLC member  220 - 2  may be attached to the front surface of the first PDLC member  220 - 1 . 
     In this case, according to the present disclosure, the PDLC members  220  may be controlled by the second-first step (see  FIG.  6   ) of applying the electric current so that the entire region of the second PDLC member  220 - 2  transmits the light and only a partial region of the first PDLC member  220 - 1  transmits the light for a second-first time (fourth time period). In this case, the light distribution pattern formed by the lamp according to the present disclosure may be formed by the light transmitted only through the partial region of the first PDLC member  220 - 1 . For example, a light distribution pattern in which a plurality of triangular light distribution patterns is arranged in one direction may be formed on the road surface by the first PDLC member  220 - 1 . 
     Meanwhile, in addition to the first PDLC member and the second PDLC member, the PDLC members  220  may further include a third PDLC member  220 - 3  provided to be in contact with a front or rear surface of the second PDLC member  220 - 2 . For example, the third PDLC member  220 - 3  may be attached to the front surface of the second PDLC member  220 - 2 . 
     In the case in which the PDLC members  220  according to the present disclosure further include the third PDLC member  220 - 3 , the electric current may be applied in the second-first step so that the entire region of the second PDLC member  220 - 2  and the entire region of the third PDLC member  220 - 3  transmit the light and only a partial region of the first PDLC member  220 - 1  transmits the light for the second-first time. In this case, as described above, the light distribution pattern formed by the lamp according to the present disclosure may be formed by the light transmitted only through the partial region of the first PDLC member  220 - 1 . 
     Meanwhile, in the case in which the PDLC members  220  include the third PDLC member  220 - 3 , in addition to the second-first step, the PDLC members  220  may be controlled by a second-second step (see  FIG.  7   ) of applying the electric current so that the entire region of the first PDLC member  220 - 1  and the entire region of the third PDLC member  220 - 3  transmit the light and only a partial region of the second PDLC member  220 - 2  transmits the light for a second-second time (fifth time period) after the second-first time. In this case, the light distribution pattern formed by the lamp according to the present disclosure may be formed by the light transmitted only through the partial region of the second PDLC member  220 - 2 . For example, a light distribution pattern in which a plurality of straight light distribution patterns is arranged in one direction may be formed on the road surface by the second PDLC member  220 - 2 . 
     Meanwhile, in the case in which the PDLC members  220  include the third PDLC member  220 - 3 , in addition to the second-first step and the second-second step, the PDLC members  220  may be controlled by a second-third step (see  FIG.  8   ) of applying the electric current so that the entire region of the first PDLC member  220 - 1  and the entire region of the second PDLC member  220 - 2  transmit the light and only a partial region of the third PDLC member  220 - 3  transmits the light for a second-third time (sixth time period) after the second-second time. In this case, the light distribution pattern formed by the lamp according to the present disclosure may be formed by the light transmitted only through the partial region of the third PDLC member  220 - 3 . For example, a light distribution pattern in which a plurality of L-shaped light distribution patterns is arranged in one direction may be formed on the road surface by the third PDLC member  220 - 3 . 
     According to the present disclosure, the lamp for a vehicle may include the plurality of PDLC members in a forward/rearward direction, thereby implementing various types of light distribution patterns. That is, in order to form a predetermined light distribution pattern, the electric current is controlled such that the light may be transmitted only through the region in which the PDLC member capable of forming the predetermined light distribution pattern has a shape corresponding to the predetermined light distribution pattern, and the light may be transmitted through the entire regions of the remaining PDLC members. Therefore, it is possible to implement various types of light distribution patterns. 
     Meanwhile, all the above-mentioned first-first, first-second, and first-third steps and the second-first, second-second, and second-third steps may be applied to the lamp according to the present disclosure. More specifically, the above-mentioned first-first, first-second, and first-third steps may be performed to implement light distribution patterns having dynamic shapes over time by using the single PDLC member. The above-mentioned second-first, second-second, and second-third steps may be performed to different types of light distribution patterns that perform different functions over time when the plurality of PDLC members is provided. 
     Vehicle 
     A vehicle according to the present disclosure may include the lamp  10  for a vehicle. In this case, the lamp  10  may include: the light source  100  configured to emit light; and the pattern conversion unit  200  disposed in front of the light source  100  and configured to form the light distribution patterns of the plurality of types by receiving the light emitted from the light source. The pattern conversion unit  200  may include: the light-transmitting member  210  disposed to face the light source  100  and configured to transmit the light emitted from the light source  100 ; and the polymer dispersed liquid crystal (PDLC) member  220  provided to be in contact with one surface of the light-transmitting member  210 . 
     The lamp may be a backup guide lamp, a turn-signal lamp, or a welcome guide lamp. The detailed description for the lamp provided in the vehicle according to the present disclosure may be replaced with the above-mentioned description for the lamp for a vehicle according to the present disclosure. 
     The present disclosure has been described with reference to the limited embodiments and the drawings, but the present disclosure is not limited thereto. The present disclosure may be carried out in various forms by those skilled in the art, to which the present disclosure pertains, within the technical spirit of the present disclosure and the scope equivalent to the appended claims.