A window covering for natural illumination of building interiors by redirecting the incident daylight at angles that promote its deeper penetration into the interior space. The window covering comprises an optically transmissive, flexible polymeric sheet having a layered structure with a light diffusing output surface and a number of total internal reflection surfaces incorporated into its material. The total internal reflection surfaces are dimensioned such that the multi-layer sheet diffusely redirect at least a portion of light towards a direction which is generally not coincident with the incidence direction.

A window covering for natural illumination of building interiors by redirecting the incident daylight at angles that promote its deeper penetration into the interior space. The window covering comprises an optically transmissive, flexible polymeric sheet having a layered structure with a light diffusing output surface and a number of total internal reflection surfaces incorporated into its material. The total internal reflection surfaces are dimensioned such that the multi-layer sheet diffusely redirect at least a portion of light towards a direction which is generally not coincident with the incidence direction.

A curtain hanging assembly that consists of a curtain assembly able to effect horizontal opening and closing of curtains, and includes two elastic motor units provided with elastic feedback. Interactive dynamics between the two elastic motor units, through linear linkage, respectively cause torque forces produced to be in mutual opposition, enabling the let down area of the curtains to be naturally fixed at any height position.

Retractable roof and/or wall panels are disclosed herein. Such panels may be used as roof or wall portions for tents or other temporary structures allowing for variable outdoor exposure and easy transitions from indoor to outdoor spaces.

The present invention provides an under-structure of a blind apparatus.

An under-structure of a blind apparatus according to an embodiment of the present invention includes: a first bar that holds the lower end of a screen; a plug that is coupled to an end of the first bar and has a first through-hole at the center; a second bar that receives the first bar and has a slit through which the screen comes out; a cover that is fixed to an end of the second bar and has a second through-hole communicating with the first through-hole; and a wrench plug that is coupled to the outside of the cover and is fitted in the first through-hole through the second through-hole to transmit torque.

The present invention provides an under-structure of a blind apparatus.

An under-structure of a blind apparatus according to an embodiment of the present invention includes: a first bar that holds the lower end of a screen; a plug that is coupled to an end of the first bar and has a first through-hole at the center; a second bar that receives the first bar and has a slit through which the screen comes out; a cover that is fixed to an end of the second bar and has a second through-hole communicating with the first through-hole; and a wrench plug that is coupled to the outside of the cover and is fitted in the first through-hole through the second through-hole to transmit torque.

A window covering can be configured to facilitate height adjustment of window covering material. In some embodiments, a handle or clips may be utilized to help maintain the position of the window covering material so that the use of an operator cord and/or exposed lift cords can be avoided or minimized.

A window covering can be configured to facilitate height adjustment of window covering material. In some embodiments, a handle or clips may be utilized to help maintain the position of the window covering material so that the use of an operator cord and/or exposed lift cords can be avoided or minimized.

A retractable curtain system is provided and includes a curtain support system, a curtain, and a retraction system. The curtain support system includes a pair of outer walls and an upper frame to provide a curtain receiving space. The curtain covers the curtain receiving space and includes a first non-transparent panel and transparent panel connected to the first non-transparent panel. The retraction system is connected to the curtain to lower and raise the transparent panel.

A retractable curtain system is provided and includes a curtain support system, a curtain, and a retraction system. The curtain support system includes a pair of outer walls and an upper frame to provide a curtain receiving space. The curtain covers the curtain receiving space and includes a first non-transparent panel and transparent panel connected to the first non-transparent panel. The retraction system is connected to the curtain to lower and raise the transparent panel.