What is claimed is:
1. A sheet-like light source device of edge-light type comprising at least a light source, a light-conducting plate and a retention member for retaining the light-conducting plate, wherein at least one convex portion or concave portion is provided on a lateral surface portion of the light-conducting plate other than a light-incident portion with the light-conducting plate being held in a specified positional relationship by means of the retention member formed with a concave portion or a convex portion which fits with the convex portion or concave portion of the light-conducting plate, and wherein a light-absorbing means is provided on at least a surface portion of either surface of the concave portion or convex portion of the retention member which opposes the light-incident portion of the light-conducting plate.
2. The sheet-like light source device of claim 1, wherein the light-absorbing means comprises a colored coating or a colored film.
3. The sheet-like light source device of claim 1, wherein the light-absorbing means comprises a colored resin molded body.
4. The sheet-like light source device of claim 3, wherein the colored resin molded body is a resin molded body formed by two-colored molding.
5. The sheet-like light source device of claim 1, wherein the light-absorbing means comprises a colored tape.
6. A sheet-like light source device of edge-light type comprising at least a light source, a light-conducting plate and a retention member for retaining the light-conducting plate, wherein at least one convex portion or concave portion is provided on a lateral surface portion of the light-conducting plate other than a light-incident portion with the light-conducting plate being held in a specified positional relationship by means of the retention member formed with a concave portion or a convex portion which fit with the convex portion or concave portion of the light-conducting plate, and wherein a light-transmitting means is provided on at least a surface portion of either surface of the concave portion or convex portion of the retention member which opposes the light-incident portion of the light-conducting plate.
7. The sheet-like light source device of claim 6, wherein the light-transmitting means comprises a transparent resin molded body.
8. The sheet-like light source device of claim 7, wherein the transparent resin molded body is a resin molded body formed by two-colored molding.
9. A sheet-like light source device of edge-light type comprising at least a light source, a light-conducting plate and a retention member for retaining the light-conducting plate, wherein at least one convex portion or concave portion is provided on a lateral surface portion of the light-conducting plate other than a light-incident portion with the light-conducting plate being held in a specified positional relationship by means of the retention member formed with a concave portion or a convex portion which fit with the convex portion or concave portion of the light-conducting plate, and wherein a light-absorbing means is provided on at least a surface portion of a light emitting surface of either surface of the convex portion or concave portion of the light-conducting plate.
10. The sheet-like light source device of claim 9, wherein the light-absorbing means comprises a colored coating or a colored film.
11. The sheet-like light source device of claim 9, wherein the light-absorbing means comprises a colored resin molded body.
12. The sheet-like light source device of claim 11, wherein the colored resin molded body is a resin molded body formed by two-colored molding.
13. The sheet-like light source device of claim 9, wherein the light-absorbing means comprises a colored tape.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
What is claimed is:
1. A semiconductor memory device, comprising:
bit lines which transfer data of memory cells;
a plurality of first sense amplifier circuits connected to odd-number lines of said bit lines;
a plurality of second sense amplifier circuits connected to even-number lines of said bit lines; and
a clamp-voltage generation circuit which supplies a first clamp voltage to said first sense amplifier circuits, and supplies a second clamp voltage to said second sense amplifier circuits, whereby during test operation, the odd-number lines are clamped to the first clamp voltage, and the even-number lines are clamped to the second clamp voltage.
2. The semiconductor memory device as claimed in claim 1, further comprising a mode-detection unit which detects a type of a test mode based on a code signal supplied from an exterior of said semiconductor memory device, wherein said clamp-voltage generation circuit generates the first and second clamp voltages according to the type of a test mode detected by said mode-detection unit.
3. The semiconductor memory device as claimed in claim 1, wherein lines of said first sense amplifier circuits alternate with lines of said second sense amplifier circuits in terms of arrangement thereof in a memory core circuit.
4. The semiconductor memory device as claimed in claim 1, further comprising a word decoder which selects all word lines during the test operation, thereby applying the first clamp voltage to a given storage point and applying the second clamp voltage to a storage point adjacent to the given storage point.
5. The semiconductor memory device as claimed in claim 1, further comprising a word decoder which decodes a row address to select a corresponding word line during normal operation, and selects all word lines during the test operation.
6. The semiconductor memory device as claimed in claim 1, wherein said clamp-voltage generation circuit supplies a common precharge voltage to both said first sense amplifier circuits and said second sense amplifier circuits during normal operation, and generates the first and second clamp voltages in accordance with a test mode during the test operation.
7. The semiconductor memory device as claimed in claim 1, wherein said clamp-voltage generation circuit generates the first and second clamp voltages varying depending on a type of a test mode.
8. The semiconductor memory device as claimed in claim 1, wherein any given sense amplifier circuit of the first and second sense amplifier circuits is connected to two bit lines, which are provided with respective memory cells forming a pair of memory cells each for one-bit data, one of the pair of memory cells storing therein data, and another one of the pair of memory cells storing an inverse of the data.
9. A semiconductor memory device, comprising:
bit lines; and
a clamp-voltage generation circuit which generates first and second clamp voltages, wherein during test operation, odd-number lines of said bit lines are clamped to the first clamp voltage, and even-number lines of said bit lines are clamped to the second clamp voltage.
10. The semiconductor memory device as claimed in claim 9, wherein the first clamp voltage differs from the second clamp voltage.