Patent Publication Number: US-8534860-B2

Title: Display light box with programmably separately-lit compartments

Description:
FIELD OF THE INVENTION 
     The present invention relates to display light box. 
     BACKGROUND OF THE INVENTION 
     Traditional light boxes comprise one or more compartments, uniformly and statically lit. U.S. Pat. Nos. 6,042,243, 6,823,618, 7,766,536, and 5,573,328 proposed several typical designs of the kind. 
     U.S. Pat. No. 4,511,953 proposed a light box with parallel secondary walls dividing the compartments and with a pivotally engaged cover. When graphic is displayed, such as in U.S. Pat. No. 7,278,770, a single uniform light source illuminates the entire panel. 
     When various portions of the display need to be illuminated in sequence, neon lights are widely used. Compared to LEDs, the graphical representations using neon lights are less complex. In addition, the neon lights consume more electricity and are hard to repair. 
     LEDs themselves are used as displays directly in some designs (U.S. Pat. Nos. 4,929,936 and 7,086,769). 
     The present design unitizes LEDs and a controller to allow a color graphic image to be illuminated region by region in any sequence and at various light intensities and patterns (by turning on and off the LEDs in the compartment at a certain pattern) to attract viewers&#39; attention to various parts of the image, as well as the light box as a whole. 
     SUMMARY OF THE INVENTION 
     The present invention comprises several compartments with partitioning walls shaped according to a translucent image on a frontal display panel, and illuminated by LEDs installed a certain distance back from the frontal display panel on a back panel onto which the partitioning walls are installed to accomplish the uniformity of light on the frontal display panel. The type and number of LEDs are determined by the required light intensity level of the translucent image. 
     LEDs are driven by a programmable controller which turns on and off the LEDs in any predetermined sequence to present a changing artistic display. 
     The light box comprises a frontal frame and a body, which further comprises four side walls and a back wall. Although the back panel and the back wall are separate in the preferred embodiment, the back wall could be used as the back panel. The frontal frame and the body are made of appropriate materials according to the location where the light box is installed, e.g., indoors vis-à-vis outdoors. A rubber frame is placed between the frontal frame and the body. 
     The surfaces of the partitioning walls and the inside surfaces of the side panels and the back panel, where the LEDs are installed, comprise light reflective materials to reduce the absorption of light by the surfaces, in order to increase the efficiency of the light box. 
     The LEDs and the controller are powered by a power source. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of the light box. 
         FIG. 2  is an exploded view of the light box. 
         FIG. 3  is the block diagram of the electronic circuit. 
         FIG. 4  shows the traditional design of the LED units where electrical current is regulated by resistors. 
         FIG. 5  shows the preferred design of the LED units where electrical current is regulated by CRDs. 
         FIG. 6  shows an alternative preferred design of the LED unit where electrical current is regulated by transistor circuits. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  and  FIG. 2  show the present invention comprising a frontal frame  1 , a body  2 , a rubber ring  3 , a frontal display panel  4 , a back panel  5 , partitioning walls  6 , LEDs  7 , and a controller  8 . The body comprises a back wall  9  and four side walls  10 . In alternative embodiments, the back wall could also be used as the back panel. Or, four separate side panels may be used inside the four side walls. 
     The frontal display panel  4  comprises a translucent image. In the preferred embodiment, the frontal display panel  4  comprises the translucent image sheet, attached to the inside of the transparent frontal display panel  4 . The translucent image is divided into several regions. Partitioning walls  6  are installed along the edges of the regions. Therefore, the LEDs in each region only illuminate the corresponding region. According to the artistic design, LEDs are turned on and off in certain patterns to accomplish a changing artistic view. 
     The light box can be powered by any power source, including 110VAC power, rechargeable batteries, or rechargeable batteries with one or more solar panels. In one of the preferred embodiments, as shown in  FIG. 3 , 110VAC power is converted to 12VDC which is supplied into the controller. 
     The surfaces of partitioning walls  6  and the inside surfaces of the back panel  5  and four side walls  10  are made of light reflective materials to enhance the efficiency of LEDs and accomplish more uniform light on the frontal display panel  4 . In a preferred embodiment, the back panel  5  and four side walls  10  are made of polished aluminum plates, which reflex light and also conduct heat. 
     The partitioning walls  6  separate individual compartments so they can be illuminated separately. In the best embodiment, the partitioning walls  6  are made of thin reflective metal sheets. The LEDs  7  can be affixed to the back panel  5  by any replaceable means, such as fasteners (e.g., screws, clips, etc.) or adhesives (e.g., silicone glue). Several LEDs can be connected together in series with a regulator, which could be a resistor ( FIG. 4 ), a CRD (Current Regulative Diode) ( FIG. 5 ), or a transistor circuit ( FIG. 6 ), to form a LED unit, and then connected in parallel ( FIGS. 3 ,  4 ,  5 ) to the I/O port ( FIG. 3 ) of the controller  8 . 
     In the resistor design ( FIG. 4 ), resistors consume power. In addition, the resistance varies according to the ambient temperature, which, for an out-door sign, could range from burning summer to freezing winter. Using CRDs or transistor circuits as regulators saves power. 
     For artistic effects, for example, LEDS in the same compartment may be separated into different groups to make the light intensity changeable. Alternatively, LEDs in the same compartment may be turned on and off in certain patterns to create certain visual effect (e.g., turned on and off row by row to create a flowing visual effect). 
     The material of the frontal frame  1  and the body  2  can be selected according to the location where the light box is installed (e.g., indoors vis-à-vis outdoors). 
       FIG. 3  shows the diagram of the controller. The standard power converter  11  of sufficient amperage capacity converts 110VAC to 12VDC which powers both the controller and the LEDs. The controller comprises an oscillator, a central processing unit, a memory unit, and I/O port. According to programs and data stored in the memory unit, the central processing unit controls I/O port, which supplies power to the LEDs  7 . 
     When the light box is used in certain places, such as on a shop window or as a free-standing outdoor sign, it may be desirable to make it double-sided by attaching two light boxes back to back. For instance, when a double-sided light box is used on shop window, it may be desirable to use a traditional static design on the inside so customers would not be distracted, and use the present invention facing outside to attract the attention of passers-by. When a double-sided light box is used in the free-standing outdoor sign, it may be preferable for both sides to use the present invention.