| 摘要 |
A composite panel or the like comprises (a) a sheet of transparent material e.g. glass or plastic, having at least one face thereof formed with a multiplicity of spaced, screen-defining surfaces which are angularly disposed with relation to intervening surfaces, and a reflective screen formed in situ on the sheet by reflective coating material applied to the spaced, screen-defining surfaces whereby the intervening surfaces define light transmitting apertures in the screen or (b) a sheet of transparent material of substantially uniform thickness having a multiplicity of spaced indentations or depressions formed in one face thereof, and a reflective coating material applied to surfaces of the indentations or depressions, uncoated areas of the face between the indentations or depressions defining light transmitting apertures in the screen; the indentations or depressions may comprise two groups of spaced parallel grooves arranged at different angles whereby the two groups of grooves intersect and define spaced parallel rows of diamond shaped screen apertures between them, and each of the grooves has at least one of its sides extending obliquely towards the opposite face of the transparent sheet. The reflective screen may be formed of metal e.g. aluminium, by chemical deposition, vacuum metallising or by spraying. The panel may have a protective sheet of transparent material covering the face of the transparent sheet. The screen may define substantially parallel rows of spaced light transmitting apertures, the apertures and intervening portion of the screen may be of the order of 0.2 inch in width, and the spaced apertures in each row may be staggered relatively to the apertures in the contiguous rows on opposite sides thereof. The screen may comprise a number of spaced substantially parallel elements which extend obliquely from the face of the transparent sheet towards the opposite face thereof so as to present a louvre-like appearance when viewed in side elevation. The obliquely-extending elements may be (a) arranged in a number of parallel rows each comprising a number of the elements arranged in spaced relationship, (b) formed on a surface of a corresponding indentation or depression of undercut form in the respective face of the transparent sheet, or (c) formed on an inclined surface of a corresponding indentation or depression in the respective face of the transparent sheet, the indentation or depression being open for the full width of the respective elements as viewed from the front of the panel. The screen may comprise a number of spaced, generally parallel elements of sinuous shape when viewed from the front, the sinuous elements when viewed in side elevation being substantially parallel and extending obliquely from one face of the sheet towards the opposite face thereof so as to present a louvre-like appearance, and wherein the spaced crests of each sinuous element merge into the troughs of the sinuous element contiguous thereto whereby a row of spaced apertures is formed between them, and whereby the apertures in each row thereof are staggered relatively to the apertures in the contiguous row on each side thereof. A composite panel or the like comprises (a) two composite panels as described above arranged one behind the other with the respective screens on the adjacent inner faces thereof, the screens being shaped and mutually arranged whereby they constitute mating portions of a single composite screen, or (b) two sheets of transparent material arranged one behind the other in parallel relationship, each of the sheets having the face which is adjacent the other sheet formed with a multiplicity of spaced indentations or depressions and a reflective screen formed in situ on the sheet by reflective coating material applied to surfaces of the indentations or depressions, the screen being thus formed partly on each of the sheets and wherein uncoated areas of the adjacent faces of the sheets, between the indentations or depressions therein, define light transmitting apertures in the screen. A thin reinforcing sheet of transparent plastic material may be interposed between and secured to the two transparent sheets on which the screen is formed. |
