| Number | Name | Date | Kind |
|---|---|---|---|
| 2405960 | Land | Aug 1946 | |
| 3064523 | Meltzer | Nov 1962 |
| Number | Date | Country |
|---|---|---|
| 0119260 | Sep 1979 | JPX |
| Entry |
|---|
| Houston, Jr., "Optical Systems Manufacturing Technology", Optical Engineering, 7/8-1974, vol. 13, No. 4, pp. 160-161. |
| Price, "Collimated Light Beam Expander-Compressor", Xerox Disclosure Journal, 9/10-1981, vol. 6, No. 5, pp. 253-254. |